To give you some more information how much impact culling these features has, I have compiled a bit of actual usage data.
1) DisarmersIchoTolot sent me one of his unreleased levels using a disarmer, but again with slight terrain changes, the disarmer could be replaced with other skills (though IchoTolot tells me, my solution is still a backrotue).
Similarly for the Introduction level "'Fixed Ascent": One could easily create a very similar level with a climber who has to dig down pillars or gliders that spend time bridging gaps, or...
I agree with this. I feel like the skill has potential even though it is underused atm.
In comparison to other skills it's also extremely fast and doesn't introduces new backroutes easily. It also can be a good delaying skill.
Well, if it has potential, then I haven't really seen it yet. It's also true, that it has some nice features, but again they doesn't really seem to be useful regarding creating new puzzles.
-if a zombie were a disarmer, It'll fix a dead trap
-have a locked/Dead option for traps and exits
-locked exits without switch(es) would need a disarmer to open them
-and dead traps would be auto-disarmed upon starting the level (Redundacy I know but hear me out) you can set it up in such a way that Zombie puzzles may be wider in their horizon
Zombie-disarmers already disarm traps (as far as I know), but this, too, turned out to be barely useful. All other ideas add new types of objects with new complexity. These new types all feel of questionable usefulness to me, so I would rather spend some time implementing other more wanted new features.
I went through three packs to list all of their disarmer levels:
Candy Mountain (Bumpy 11): Same idea would work with building over the traps.
Overclocked Lemmings (Insane 19): Without the disarmer and the traps, the level would remain largely the same. Just some timing issues would become far easier.
Squishy and Splodey (Clam 9): Introductory level to disarmers. Not really anything special.
Sewer rodents (Calm 22): It's an 20-of-everything level that has a lot of different solutions, even without disarmers. Actually one could make a case that it becomes more interesting without disarmers...
Freeze frame (Perky 4): The main idea here doesn't need disarmers at all.
YumYums (Twitchy 6): Currently possible without disarmers. As this is a classical "contain crowd while one worker lemming creates the path" removing the disarmer would make the leel even more interesting.
To each his own (Twitchy 10): The disarmer created a backroute here. See the replay I will post soon in the level pack's topic.
Operations: Super Rescue (Twitchy 18): Again the level would work equally well without the disarmer, if one removes the traps right next to the exit.
Taming the beast (Harmless 12): Mainly an intro level to disarmers. It's repeat is the actual puzzle level and doesn't give you disarmers.
Twilems (Harmless 16): Here the disarmer adds nothing to the level - just turn the first lemming coming to the only trap into a disarmer.
Praise Kek (Harmless 23): A level with multiple solutions. Replacing the disarmer with another skill doesn't take anything away from the level, in my opinion.
The Phantom Lemace (Harmless 25): One disarmer and one trap.
The Path of Senses (Harmless 29): One disarmer and one trap.
Torture Pit (Disturbing 5): Lots of traps for the disarmer to work on. But the level would basically play the same if one would give the worker-lemming other stuff to do.
Have you seen my screwdriver? (Disturbing 10): This is (supposed to be) a level about getting the disarmer pick-up skill. While it needs in its current form the disarmer, one could replace it with a climber if one changes the terrain a bit.
All lemmings must die (Disturbing 29): 10 disarmers for just one poor dragon is overkill...
Throw me a lifeline (Disgusting 15): One disarmer and one trap.
Mary had a little lem (Disgusting 17): A multiple solution level, where giving a disarmer makes sense. Still it's only there for convenience.
In memory of Steve Irwin (Disgusting 18): This has a disarmer pick-up skill, but so far away that it is simpler to solve the level without it in my opinion.
Ready for takeoff (Abhorrent 10): This gives a disarmer pick-up skill, but I don't see any way to even get to the traps...
Luring lemming into mouse trap (Abhorrent 12): Apart from a backroute, that doesn't touch the disamer pick-up skill, this would work equally well if one replaces the traps by water.
Attack of the Clones (Demented 12): Depending on the solution used, the one disarmer and the two traps might pose a problem. But the level works equally well without the disarmer.
Halt the execution (Demented 18): If one wouldn't have the disarmer skills, one could just use two builders to bridge the trap. Nothing more would change.
Parkour of Pain (Demented 23): Having only one lemming and a disarmer skill, having traps to disarm around seems pretty redundant.
Six heroes, one destiny (Demented 25): While having a disarmer, it's not really of much use.
It's FEEDING Time (Demented 29): This has a disarmer pick-up skill, but so far away that it is simpler to solve the level without it in my opinion.
Summary: 26 of 305 levels use the disarmer skill. But of those only one or two are better off with the disarmer. Most work equally well with just the other skills.
3) Radiation objectsAgain I list the usage in the three level packs:
Cosmic Ray Zone (Bumpy 2): Intro level. More annoying than interesting, in my opinion.
Lem Youe Lem Could Small Like (Bumpy 17): Slight terrain and skill changes would enforce the same solution, even without the radiation object.
A Universal Production (Twisted 14): That's a pretty nice level and requires radiation objects.
Ooh, Shiny! (Insane 4): This level, too, relies on radiation objects,.
Tick-Tock lemmings (Perky 1): Introductory level to radiation objects.
Lem in da hood (Perky 7): Just uses them like fire traps.
Two for the price of one (Perky 11): Yes, nice use there.
Thou dost ask too much (Hyper 4): Nice use of the radiation object there, but the level doesn't require it, as far as I can tell: Remove the radiation object and one walker, add a triggered trap at the radiation object's position and give a second miner.
Strato Incendus's 'Paralems' (150 levels)
Lethal dose (Disturbing 18): This is more about placing times bombers correctly, than about radiation objects.
One-man building company (Disgusting 11): A gap would have worked equally well here.
Dispose of failed exemplars (Abhorrent 29): Essentially the same as "Lethal Dose".
Attack of the Clones (Demented 12): Given the save requirement, it's basically used as a trap.
Only over their dead bodies (Demented 13): This makes actually good use of the radiation object.
Detonate on collision (Demented 17): If one replaces the radiation object with a pick-up bomber, the only change would be that the timing is a lot easier.
Summary: 14 of 305 levels use a radiation object. About half of them use it in rather creative ways. But is usefulness in about 2.3% of all levels enough reason to keep it, especially as it introduces timing issues?
4) Slowfreeze objectsApart from the two levels in
Casualemmings, I don't know of any level, that makes good use of them. Paralems has a few levels using them as continuous traps, and I haven't seen it LemPlus IV. That makes the slowfreeze objects even less useful than radiation objects.