I'd say the specific vibe of the original styles is mainly due to:

1/ A limited color palette.
2/ Not too detailed pieces that can easily be combined to make larger structures.

The original tilesets were like a toolbox to build anything. The feeling of the Tribes tilesets was quite different, probably because they contain whole recognizable objects as terrain pieces.

Thank you Armani!

I'm locking this topic now (see note in the first message) but I'll check all your replays and come back to you in the private messages

Well, something happened. Dodochacalo is still around! We'll try to merge our levels into a bigger pack than this one. He's got around 30 levels so this would make for an 80 levels pack, which is quite fine.
We'll take some time to order levels and fix what needs to be fixed, then we can release it. The pack would probably be updated if we happen to make more levels in the future

I usually try to find new or interesting ways to use skills, or to make cool "choreographies" happen. Difficulty tends to come naturally when you try to get off the beaten path. That being said, don't make hard levels for the sake of difficulty only. Your main goal should be to make your levels engaging and/or surprising and/or gorgeous to look at

The following levels have been fixed to prevent David's backroutes. Since then he solved all of them as intended, which is neat but I'm sure some backroutes still remain

Posh 03 - Second-Hand Wonderland
Posh 05 - Swim Swap Swoop
Posh 09 - Bridges in the Sky
Pedantic 04 - Land of Confusion
Piquant 05 - Satanorium
Piquant 07 - Forbidden Friendship
Piquant 10 - False Happiness
Pompous 01 - Emeraldpunk 5047
Pompous 02 - Rickety Business
Pompous 04 - Deus Ex Machina
Pompous 06 - Itinéraire Touristique
Pompous 07 - A tad mad, a tad rad!

I updated the attachment in the first message.

Pieuw, I finally solved Piquant 3 (see replay) . However, I didn't use the kaywhyn trick and I didn't use the climber skill. So I think this is a backroute. I’ll be curious to know the intended solution. For me, this is the hardest level in the pack.

This is a backroute indeed. If a solution requires such frame-by-frame "messy"skills assignment, you can safely assume this isn't what I intended Nevertheless, well done! You found a working solution and it's fine.
I really don't think this level is that hard, the intended solution is easy to execute and doesn't require any hard trick. It may be hard to figure out though

I didn't think there were so many backroutes in my solutions. In fact, as you specified that the progression curve was not "smooth", I wrongly thought that the difficulty was quite random. So, I wasn’t surprised to find rather easy levels in the last rank, and vice versa. Indeed, some levels in the first rank seemed quite difficult to me (Prosaic 7, Prosaic 8, and especially Prosaic 10).

The levels are ordered by ranks which are meant to get harder and harder. I just sorted them pretty quickly based on my perspective only so this is why I said the difficulty curve may be bumpy. Also, the first rank gets a bit hard very quickly because I didn't really make easy levels except for the first two.

My solution for Piquant 10 is therefore a huge backroute! It took me many hours to solve this level. Again, I would be curious to know what the intended solution is. It was, with Piquant 3, the level that was the most difficult for me to solve.

False Happiness requires a very specific trick to be solved. You didn't use it so your solution is a backroute but this doesn't mean this is a bad solution. You got many things right, too! I'm impressed you spent hours on it, I hope it didn't drive you crazy!

Would you like me to send you replays to these levels (Piquant 3, Piquant 10, Pompous 7)? Maybe more?. Or would you prefer some clues to try and solve them another way? You can PM me anytime

@David After taking a look at my replay I can confirm Piquant 3 is solvable without any weird / fiddly trick nor extreme timing. I'm sure you'll manage to solve it eventually as you managed to beat the hardest levels of the pack

I also watched your replays, here's my feedback:

These were slightly backroutish but felt OK
Prosaic 10 - Low Tide
Pedantic 03 - From A to B and Back Again
Pedantic 08 - Dual Flavored Swirls
Pedantic 10 - Cabinet of Curiosities
Pompous 05 - Hypostyle Freestyle
Pompous 09 - Funhouse Shmunhouse

These were backroutes but the levels are broken anyway
Posh 04 - As not easy as it doesn't look
Pedantic 07 - Maintenance Staff on the Loose
Piquant 04 - Take Five

Huge backroutes
Posh 03 - Second-Hand Wonderland
Posh 05 - Swim Swap Swoop
Posh 09 - Bridges in the Sky
Pedantic 04 - Land of Confusion
Piquant 05 - Satanorium
Piquant 07 - Forbidden Friendship
Piquant 10 - False Happiness
Pompous 01 - Emeraldpunk 5047
Pompous 02 - Rickety Business
Pompous 04 - Deus Ex Machina
Pompous 06 - Itinéraire Touristique
Pompous 07 - A tad mad, a tad rad!

Puzzles you solved perfectly
Prosaic 03 - Quid Pro Quo
Prosaic 04 - Format Semantics of Modal Logics (though you could have saved lots of time here)
Prosaic 06 - Smell Like Team Spirit
Posh 01 - Paucity
Posh 06 - Dos and Dents (thinking this one should have been placed later because of the intended trick)
Posh 07 - Convoi Prioritaire
Pedantic 01 - Return to the Shire
Pedantic 02 - Novelty Act
Pedantic 05 - Ethereal Refinery
Pedantic 06 - Razing the Foundations
Piquant 01 - Viaduc Caduc
Piquant 06 - Precarious Guidance System
Piquant 08 - The Diving Board
Piquant 09 - Attack of the Big Root Thingies
Pompous 03 - Structure of Matter
Pompous 08 - Shelf Control
Pompous 10 - Horus's Reaching Hand

The other levels were either open-ended or close enough to the intended solution. Well done solving (almost ) all of them!

I may take some time in the near future to fix some backrouted levels, especially the ones I like the most.