I've been doing some more playing, re-read a lot of the discussion in this forum and I'd like to highlight a few things and share some opinions. It would be good to hear people's thoughts and have some discussion on the problems/solutions I've outlined. A few of these are my own observations & ideas, a few I've read elsewhere and what's been pointed out has resonated with me enough to warrant repeating it.
Sorry about the length, but I've aimed to be as dense & concise as possible and tried to break it up a bit to avoid wall of text syndrome.
1 - Dretch vs rifle balance:Norf has said a few times he remains unconvinced there's a problem here, but I'm very much coming around to the view that the dretch really is too weak vs a rifle, even for its value. This is an extremely crucial part of gameplay to get right, not just for s1 but for the entire match, so I'm still going to chip in.

A moderately skilled naked rifle can usually take out a dretch given a second or 2 with line of sight, or if he's able to anticipate where the alien is likely to be. Therefore in order for dretches to secure kills they have to rely a lot on the human screwing up (either by letting themselves be ambushed or by just plain sucking at aiming). I know its not quite as simple as that, but a dretch's usefulness quickly reaches a ceiling regardless of player skill, and after that it mainly depends on the human. This is not so fun for the dretch, and lets humans dictate the game for the first few minutes. Relying on pub human feeding and free evos for aliens getting off the mark is not ideal.
This is a two part thing: the weakness in many circumstances of the dretch, and the usefulness of the rifle. A dretch buff wouldn't hurt the rest of the game either - after s2 the dretch takes a nose dive in usefulness due to helmets etc in a way that the trusty old rifle doesn't really.
Some possible ways to help the dretch:
- Lower the value (180 -> 150) - imo a much better reflection of the true value of it as things stand
- A small but significant HP buff (25 -> 30) - would let the dretch survive a couple more tenths of a second of approaching.
- A better bite (36 -> 40) - enough for torso + headbite to kill.
As for the rifle, the easiest way to tune it would be to lower its ROF slightly (90 -> ~110). I don't like the idea of lowering damage per shot as much, as this also changes how much damage a rifle can do in one clip, which feels about right.
Also, I have a slightly more radical idea to better reflect the value of the rifle (especially the armoured rifle) by effectively making it cost 50cr or so more than it does relative to the other weapons. Obviously it must remain free at point of use, so what I'm proposing is to change the price of larmour+helm from 70+90 -> 90+120, and to reduce the price of all other weapons by 50. This means a loadout such as {lasgun, larmour, helm, battpack} would cost the same, but that an armoured rifle costs 50 more due to the lamour+helm price hike. [edit - also realised another knock on effect would be a required raise of the bsuit cost to 450 in order for everything else to remain unchanged]
I am convinced this would be a fairer and more balanced way of doing things. It has never felt right that a human can be so effective for so little cash at s2, whereas an alien has to shell out a good bit more to become an effective s2 combatant.
2 - The DC:Quite a lot of discussion has centred around how the DC should work, and how useful it really is at present. The consensus seems to be that it can be nice to have, but isn't really that important, and people would like it to do more (obviously without it making human bases too strong). Aside from the healing rate/mechanism debate, I'm proposing a secondary function for the DC: as the key to the radar in human helmets. Basically, if there's no DC up, the radar doesn't function.
This is obviously something the humans would ordinarily want to have, but isn't a crippling blow if the aliens manage to kill it, so in my mind it would put the DC in a nice bracket of importance. It doesn't really reduce the value of a helmet much, it would still be essential wear for its protection regardless. Also importantly, this isn't another new shiny feature which the humans have got and the aliens haven't - its just adding a precondition for an existing human thing. To me, this feels good.
As a side issue, the building itself feels too fragile. 190HP doesn't even require a goon to use his 3rd barb! I think being a meaningful building should go hand in hand with a modicum of resilience, perhaps 240-300HP would be good.
3 - Disincentive for camping / rewarding map control & offence:These are 2 sides of the same coin. Encouraging this I think is pretty much universally seen as a good thing and makes games more fun and dynamic. Basically I'm just plugging domination here. Map control = more free credits for rushing teams hiding in bases. It would make games more volatile though: if one team got ahead, this advantage would tend to increase, rather than fizzle out after a while.
4 - misc other• I'd like to be able to share excess credits amongst my team. Its annoying letting them go to waste, and it feels like those credits have somehow got the right to be used.

Autosharing when over the limit would be even better.
• I dislike how the multiplier for light armour varies as 0.3, 0.35 or 0.4 depending on angle. It feels needlessly overcomplicated - is there a good reason to not just replace it with 0.35?
• I'd like to be able to evolve nearer humans or their buildings. Its a fairly annoying limitation, and I can't really see how it could get abused. [edit, suggestion by celestial_rage - override the evolution denial when near the OM or on creep]
• I'd like an optional mini map in the corner of the screen. It doesn't have to have too much info on it other than your position and direction, but it would really help with navigation for new players and maps. Probably a pain for the mappers too, but it would be nice.
[edit - new addition] • Initial credits for players joining a match late. If you join when your team is s2, you get an initial free 1 evo / 222 credits. If you join when your team is s3, this is 2 evos / 444 credits. Not huge, but means you can be useful from the start, especially for aliens who would otherwise have to patiently dretch/build for a while.
Thanks for reading. Hope you agreed with some of this, or at least found some interesting things to think about.