I do think having one per each level of Fun 1-7 might be somewhat repetitive though, it would probably be more than sufficient to do one for completing Fun 1, and another for completing the entire set of tutorial levels (ie. all of 1-7)...
I would actually prefer to have even less achievements of the type "Complete ...", i.e. having only one for "Fun 1-7", "All of Fun", "All 120 levels" and perhaps 2-3 special ones. As Proxima said, it is good to have some easy achievements, but I would feel cheated if I got more than 20% of the achievements simply by completing the game.
?? ?? - Save 98% (if possible on NeoLemmix; I'll have to check) on Tricky 23
I think even 97% would make for a good achievement.
I totally second all of Proxima's suggestions for "lite" versions of challenges. Here are some more:
- Fun 10: 100% without floaters, miners or diggers
- Tricky 11: without builders (the level can be replaced, if you find a better one for this kind of achievement)
- Taxing 18: 100% without using the direct drop glitch
- Taxing 30: with only 20 diggers (instead of the current "Falling Down" achievement suggestion)
- Mayhem 13: with only 6 skills
- "Perfect Rendezvouz" Mayhem 30: save 100% (not because this is terrible interesting, but just because it feels like an achievement to save every single lemming on the final level)
- "Karoshi Master": Solve a level while killing lemmings in at least 5 different ways (e.g. on Taxing 2 you have 2 kinds of traps, drowning in water, splatting, bombing, falling out of the screen, nuking/out of time)
- "SuperLemming": Solve all levels with the Superlemming gimmick on