So, I was going to have a write up here explaining how I thought an ability tier list might go, but when I looked at the Ability Guide in the Gear tab to make sure I wasn't missing any, I noticed that they actually are pretty close to the order that I had started to write about.
I think that the raw stat boost upgrades are the best; power, defense, run speed, swim speed. Constant, instant boosts that just make you stronger.
The second tier to me is the "ammo" abilities, increasing recharge rate, decreasing main and sub usage. I would say the increased special charge rate could probably fit here too, and the extended special active time as well in situations that you have a timed special.
The third and bottom tier to me are the conditional boosts. I understand that they are there to empower comebacks, but I just rather have those slots dedicated to things that make me stronger whether I am winning or losing.
Then comes the bottom row, which as far as I've seen, are all only available as a primary (feel free to correct me on this).
Of these, the only ones I feel are really worth giving up primary boosts on one of the top tier abilities are the last two, with Stealth Jump being the only one that really stands out as very good and worth pursuing as a slot.
Those are just my early first impressions on what abilities to look for in gear and what would be desirable rolls. If a real competitive meta game of premade teams ever does develop, I notice quite a few abilities that suddenly become much much better with communication and coordination. This is all subject to change as more info comes out on how abilities stack and interact. Even just based off the diminishing returns we do know, I would say I would still rather have diminished abilities from tier 1 than a full ability from my third tier. What are you all's thoughts on abilities so far?