It's been a while, and I have more than doubled the deadline while waiting for more entries, some of which are still not finished, but here we are.

FIRST PLACE:

"Loc ll (steampunk airship)" by @CrazyCatZe

• Looks: 14/15pts
• Flight performance: 8/15pts
• Part efficiency: 9/10pts
• Realism/creativity: 9/10pts
• Features and their usability: 10/10pts
• Quality of construction: 10/10pts
• Personal impression: 8/10pts
• Description: 10/10pts
• VR compatibility: 9/10pts
  Total: 87/100

It flies more like a gyro-stabilized helicopter than an airship, and a wobbly one at that.
Other than that, I was hard pressed to find any flaws with this build. Efficient construction, beautiful design, lots of functions and features, moving parts, and everything works. Beautiful description with a story and a lot of very nice images.
I did take one point off VR compatibility even though the craft is VR curated, because controls cannot be used with a mouse as requested in the challenge.
Oh, and I did manage to catch the box and load it into the coal bunker. Very nice feature.

SECOND PLACE:

"1A. RDR2 Flying Stagecoach" by @Type2volkswagen

• Looks: 14/15pts
• Flight performance: 11/15pts
• Part efficiency: 8/10pts
• Realism/creativity: 10/10pts
• Features and their usability: 8/10pts
• Quality of construction: 9/10pts
• Personal impression: 8/10pts
• Description: 7/10pts
• VR compatibility: 9/10pts
  Total: 84/100

A beautiful little steampunk airship with tons of details and a decent lore behind it. It doesn't maneuver very well, but it is manageable. Controls seem to be laid out perfectly for VR, but they do not respond to mouse inputs.
Very nice work on sun shades, I'll be sure to remember that trick for the future.

THIRD PLACE

"Fire Nation Airship" by @BMilan

• Looks: 15/15pts
• Flight performance: 11/15pts
• Part efficiency: 8/10pts
• Realism/creativity: 9/10pts
• Features and their usability: 7/10pts
• Quality of construction: 10/10pts
• Personal impression: 7/10pts
• Description: 6/10pts
• VR compatibility: 10/10pts
  Total: 83/100

A perfect replica of the airship from Avatar, or as close as one can get with all the inconsistencies in the animation. The build is very VR friendly, with all controls being available on the bridge and usable with a mouse.
However, this being an airship from an animated series drawn by someone who doesn't know anything about airships, this was the most boring thing I ever flew. It's perfectly stable, doesn't need any adjustments. Just push a lever until you are happy with the altitude and throttle up.

4th

"ZMS Von Der Tann" by @Quartz05

• Looks: 12/15pts
• Flight performance: 10/15pts
• Part efficiency: 9/10pts
• Realism/creativity: 9/10pts
• Features and their usability: 8/10pts
• Quality of construction: 9/10pts
• Personal impression: 9/10pts
• Description: 9/10pts
• VR compatibility: 4/10pts
  Total: 79/100

Amazing build overall. It doesn't really look like an airship, as it has no visible lifting gas envelope, but it, for the most part, flies like one. Buoyancy (lift) should be preset at near neutral to make it perform more like an airship. Very creative design, very efficient use of parts and labels. It easily could have been more VR compatible with the addition of rudder wheel and throttle levers that you can grab with a mouse.
Auto-aiming is spot on, and the craft is durable enough to engage USS Beast fleet at close range. It tanks gun damage, and missiles from destroyers just keep missing it for some reason.

5th

"Imperator Class Aircraft Carrier IVS Aurora
" by @FlyingPotato_131

• Looks: 9/15pts
• Flight performance: 9/15pts
• Part efficiency: 8/10pts
• Realism/creativity: 9/10pts
• Features and their usability: 9/10pts
• Quality of construction: 8/10pts
• Personal impression: 8/10pts
• Description: 10/10pts
• VR compatibility: 0/10pts
  Total: 70/100

This entry is so big I had to bring a friend onboard to help me test it. My computer just won't load it. However, effort is obvious. Actual tunnels for side thrusters, working plane with hangar, very effective AA battery... Airship doesn't seem to respond to pitch input at all, and might have a bit too much buoyancy adjustment. It's also sluggish in turns even with thrusters. Airships were fairly good at turning due to their mass being relatively low and rudder so far from the center of mass. Description is great, even including a very nice video. VR compatibility is non-existent, while you did have a hollow bridge to put all the necessary stuff into.

6th

"Raab Karcher Oscar Huber" by @FlyingThings

• Looks: 10/15pts
• Flight performance: 12/15pts
• Part efficiency: 5/10pts
• Realism/creativity: 9/10pts
• Features and their usability: 7/10pts
• Quality of construction: 8/10pts
• Personal impression: 8/10pts
• Description: 7/10pts
• VR compatibility: 0/10pts
  Total: 66/100

Like with the other entry by FlyingThings, this one is sluggish at turning, but not as sluggish. Other than that, it flies really well.
I wasn't expecting a steamboat-inspired airship when I started the challenge, and it is a pleasant surprise to have one. Design could have been further refined, and it could have been made to have at least some VR compatibility, but it's still very nice.
Cyclic rotors work perfectly, great feature.

7th

"Rj Explorer" by @RamboJutter

• Looks: 10/15pts
• Flight performance: 8/15pts
• Part efficiency: 5/10pts
• Realism/creativity: 8/10pts
• Features and their usability: 3/10pts
• Quality of construction: 6/10pts
• Personal impression: 6/10pts
• Description: 5/10pts
• VR compatibility: 0/10pts
  Total: 51/100

A fun little blimp, though, as the description states, it flies more like a spaceship, lacking any directional stability. There are no VR features, description is short and lacks images and creativity, and there are literally no moving parts other than landing gear. Design is very interesting, very steampunk, and very typically Rambojutter.

8th

"Welcome to the Party Boat!" by @Kerbango

• Looks: 7/15pts
• Flight performance: 6/15pts
• Part efficiency: 5/10pts
• Realism/creativity: 7/10pts
• Features and their usability: 8/10pts
• Quality of construction: 7/10pts
• Personal impression: 5/10pts
• Description: 6/10pts
• VR compatibility: 5/10pts
  Total: 50/100

Interesting, and certainly unique build. Lots of flashing lights, but overly simplistic and rushed design. The ship is difficult to control, lacking directional stability. As with some other entries, lift has to be manually adjusted for neutral buoyancy, which isn't the case on airships.

9th

"Cielo Sentarse" by @OwO

• Looks: 5/15pts
• Flight performance: 2/15pts
• Part efficiency: 3/10pts
• Realism/creativity: 7/10pts
• Features and their usability: 2/10pts
• Quality of construction: 6/10pts
• Personal impression: 3/10pts
• Description: 3/10pts
• VR compatibility: 0/10pts
  Total: 31/100

Frankly, this is a helicopter that looks a bit like an airship. It doesn't behave like an airship, instead using helicopter rotors for flight. It is too directionally stable when it picks up a direction, refusing to turn. Elevators don't seem to be doing anything. There is no interior, so there is no VR compatibility.

10th
"David Class Aerial Corvette" by @FlyingThings

• Looks: 7/15pts
• Flight performance: 5/15pts
• Part efficiency: 5/10pts
• Realism/creativity: 6/10pts
• Features and their usability: 1/10pts
• Quality of construction: 5/10pts
• Personal impression: 3/10pts
• Description: 2/10pts
• VR compatibility: 0/10pts
  Total: 27/100

A very crude build. No special features to speak of, over-reliant on VTOL input for everything thus forcing the player to juggle activation groups to get anything done. I didn't manage to make it complete a 180 turn, it has a tendency to go straight.

11th

"AirWhale" by @TeodoroG

• Looks: 2/15pts
• Flight performance: 0/15pts
• Part efficiency: 5/10pts
• Realism/creativity: 2/10pts
• Features and their usability: 2/10pts
• Quality of construction: 3/10pts
• Personal impression: 2/10pts
• Description: 1/10pts
• VR compatibility: 5/10pts
  Total: 22/100

A very rudimentary build. It cannot take off, it acts as a heavier-than-air aircraft, and loses control easily in the air. Labels are not fitted to the envelope, design is extremely simplistic. It can be operated in VR, as it has both of its control inputs present in the cockpit. Still, as an airship, it needs more control inputs, like venting and ballast control, and elevator control.

"Bomb in a Bomb" by @32
Disqualified for not meeting the requirements of the challenge. Minimum part count is 500 parts.

"CCCR" by @114514cat
Disqualified for not meeting the requirements of the challenge. The build needs to be an airship, not a box.

Thank you all for participating, and congratulations to the winners!