There is just something so elegantly polished about the 3Cs setup right now. If the values are centralised, though, they don't feel it without the visual properties of the character also being centralised too. At this point, Davy's is winning me over with the googly eyes ...
Davy: well organised gym, but I'd have to agree with Nick. Difficulty is rough, longest jump doesn't feel comfortable, and it leaves me with a little concern that, although there's a great game at the heart of this, you're not quite there yet in understanding it.
Hoikei: Watch out for the gameplay effects of visuals. Your particles and screen overlay cloud the player's vision on the gas zone: a very nice touch (personally I prefer it over the damage that it also does) but you have to be aware of how that affects difficulty. Could be a very powerful LD ingredient used in the right way!
Blizzard zones are a bit tougher ... now that the character is feeling so good to play, it's apparent that it just isn't fun to be going slowly. It's inhibiting the player, but is it actually more challenging to them if they complete the level slowly? Think about what skills the player has to employ to pass it - if it's just a relative adjustment of their judgement, then once you're in the blizzard, the game is just less fun, and not more challenging ... think about another skill, like maybe timing that could be incorporated with the blizzard.
Radiation is similarly tricky as an LD ingredient. Less so, because affecting only the dash/jump means that it's like having two sets of metrics to remember - there's a challenge there (because the speed stays the same, so its not like the whole character shifts) but it'll all come down to how you use it - popping in and out of radiation clouds is going to be a challenge of your awareness and memory!
Tudor: Work with the team to get the aesthetics levelled up a little bit. Try and lock down some clear indication of different platform archetypes so players can learn them - this is the "falling" hazard, this is the "patrolling" hazard, this is the "floaty" hazard, etc.