A Farewell to Kings: Using builder+digger to make a turn around point for the climbers seems good but my solution still doesn't use any floaters.
A Real Breakthrough: This seems intended now
Another Impasse: I think this level has several possible solution. The main challenge here is letting nobody splat in the digger with well-placed builder bricks.
Another very short level: Attached two different(but similar) solutions. I like the second solution more. I think you can block my first solution by making the bottom platform lower so 4 builders are not enough to reach.
Cavelems, Clever mining, Dual Action: These levels were quite easy and straight forward. Based on the skillset, I might have backrouted Clever mining.
Hole in the Wall: This solution seems extremly cheesy but I don't see any possible way to save at least one lemming in time...
Just old fashioned building: Nice puzzle with builders and miners. The title really pit well with the level.
Pit of Doom: Attached two solutions. I think my first solution is intended. I used every single skill and save exactly 29 lemmings. I attached another solution that has a leftover skill and save 20lemmings.
Running down: This level was also very easy and straightforward.
Short Journey: Using the bomber to destroy the two layers of terrain looks fine. I have a lot of leftover skills though.