Good AA possibilities:
Thruster Pack- as is, maybe give it a bit more oomph
Higher Jump (or double jump)- This would divert power to your legs and allow you to jump higher or just a little thrust upwards after your jump. If you include fall damage in the game it would be a way to negate it if timed right.
Increase Speed - Would give you a temporary speed boost (maybe to base speed maybe to sprint, maybe to both) When activated you get a brief period of enhanced speed. if you want to pull a shadowrun, make it drain your shields. This would prevent people from using it to run away from fights.
I kinda want a 4th one so you can have everyone on the team with something different, but if it was limited to these 3 that would be fine.
It's really not that fucking hard. Player satisfaction should come from outplaying their opponent. When you out BR someone that's all the satisfaction you need. Reward the player with bragging rights and a RANK.
GTA Online has a hilarious system.The winning team will be displayed at the end and the MVP of the winning team gets to perform a gesture such as flipping you off, jerking off on you, or as simple as a salute or drinking a beer. I know it sounds silly but I strive to be the best in the match just so I can be featured flipping off the competition. So in Halo it would display your entire spartan team and the MVP of the match would be featured front and center and do some kind of "spartan like" gesture.
Having four AAs is a good idea - even if it was just for a niche gametype, it'd be interesting to have things go relatively class-based and have certain AAs work better with certain weapons. Just an idea:
-scrap DMR
-Everyone starts with a decent (but not good) Pistol, so maybe the Halo 4 edition, and an AR
-Immediately surrounding the base there are three precision rifles: Light Rifle (passive marksman), Carbine (active assault), and BR (active / passive balance), as well as some "ammo packs" for each but not more than 3 actual rifles
-Power weapons spawning on map, of course, static locations
-Four AAs to start with
Sprint: Works as usual, maybe drains shields like you said. Works well with the BR.
Thruster: Slight buff along the lines of Evade, but only one use before a recharge. Works well with Carbine.
Jump Jet: "winged" Promethean backpack that allows the user to double jump. Good for getting to vantage points, and works well with the Light Rifle.
Wildcard: A fourth (not randomized) AA designed to aid the user that doesn't get the precision rifle, but may further bolster their defenses / offenses, allowing them to get power weapons or aid their teammates.
Some examples of Wildcard AAs could include:
- a Hologram variant
- a "spotter" function that could detect the loadouts of enemies and broadcast them to teammates
- a "cleric" ability such as a mobile Bubble Shield / Regen Field that doesn't heal / shield you - only your teammates, and disappears when you die.
In addition, you could balance it so that the more players you have in your shield / regen, the more spread out power distribution gets. So for example, if you only had two people (yourself, the cleric, and one other teammate) inside a Team Regen, their regen speed would roughly be 100%; while if you had three others in the field with you, the speed would be 33%, to the point where it'd be near impossible to turtle in Big Team matches.
So while a team huddling around their Team Regen user might seem intimidating, it should be obvious who's at the exact center (and there could always be a very blatant animation / visual effect for the cleric) and picking off the medic would immediately leave the huddling enemy team vulnerable.
I'm not really sure I'd want a starting ability that works solely as a defensive option because it would slow gameplay down, but there's tons of other AA options to work with in the "wildcard" slot.
As much as I'd hate to lose Hologram, if we're going for a balanced sandbox, I think it'd scrap it as an AA and have it replace the Spartan Laser. Identical cooldown, 4 shots, etc. but no damage dealt - it just shoots out a Hologram in the direction you're pointing.
Just to completely neuter defensive options, you could also always set it up so that if Team Bubbles / Team Regens touch eachother (of any / all teams), they'll cancel eachother out, meaning you can't just pull an RTS and form a giant wall of regen fields to move onward. The way things are set up with four definitive classes, it'd allow 4v4 teams who knew what they were doing and had a balanced roster to flourish and destroy overspecialized dorks who tried running in forming a wall of Team Bubbles.