Jess Alon, I think the system of unique customizability that you propose sounds interesting and fun, but I don’t think it will be implemented in Brink and here’s my justification why:
I think Splash Damage chose the Abilities implementation that they did from a deliberate game design and accessibility perspective. Having extra layers of customizability and ‘skill trees’ is something that they mentioned specifically cutting in one of their Developer Videos.
Accessibility to new players is something that Splash Damage strove for in Brink. We can debate as to whether they’ve achieved this goal, but I feel it is a central pillar of their design philosophy with Brink, nonetheless. Extra layers of customizability at level cap only further obfuscate game mechanics in what could already be interpreted as a highly complex and fast-paced play experience.
Having said this, bear in mind that I’m only offering this perspective from the mindset that it might serve to better align your expectations with what I predict will be the eventual reality. In other words, don’t get your hopes up?
Regarding the OP, new maps would do a great deal to improve the variety of the gameplay. I think 2-3 initially to eventually 5-6 would be nice.
Likewise, I can see Brink benefiting from other play modes like a Limited Lives (per objective) or One Life (per objective) variant. However, whether these game modes are viable or not will depend, to some extent, on the degree of fragmentation in the community. I’d also support a Capture-the-Flag (CTF) map and CTF playlist for Brink.
With respect to team-play (on consoles), I would like to see a significant improvement to the support offered to players trying to party up and play together. Foremost among these improvements, I would like to see a feature where players could search for games as a group, as opposed to individually attempting to join their friend’s session.
In all honesty, though, I’d be most-happy with Brink in the near term if the announced network improvements actually resolve the issues with latency, host selection, and host migration.