One of the assumptions we've all made for Unvanquished is that it should include certain common elements of strategy games, including resource management. It's time to define what exactly we mean by "resources".
Broadly speaking, a "resource" is something that can be spent for a purpose. Since there are four things you can do in a competitive multiplayer game, we can say that a resource in Unvanquished is something that enables a team do one or more of these things, or to do them better. Furthermore, we can talk about several qualities of a resource:
How the resource is acquired
How the resource is spent
How ephemeral the resource is (is what you buy with it reusable? if the enemy can take it away, do you get your resources back? immediately?)
How transferrable the resource is (can you get a refund to spend it on something else?)
How limited the resource is (is there a limited total supply? can you only have so much at one time?)
An example: Tremulous has three resources:
Build points - Build points let you build structures, which are entirely reactive in Tremulous (you can't build a bot that goes and attacks the enemy) and hence can only be for passive defense or passive offense. (1) Build points for aliens are provided free up-front; humans get a lot this way too but can acquire more with repeaters. (2) Only builders (who are largely helpless) can spend build points. (3) Structures last until enemies destroy them, and then build points return in full over time. (4) You're free to intentionally replace one structure with another. (5) Alien build points and human reactor build points have a fixed limit; repeater build points are limited by space and reactor build points.
Funds - Funds let players upgrade themselves, which contributes to active offense and defense.* (1) They are acquired by killing enemy players. (2) Aliens can spend funds anywhere not near the enemy; humans must visit a certain structure. (3) With the exception of the grenade, upgrades bought with funds last until you die, and you don't get them back. (4) Human funds are more transferrable than alien funds (aliens get fewer evolution options every time they evolve). (5) Players are limited in how many funds they can have at one time, but are otherwise only limited by how many enemies they can kill.
Stage points - Staging up improves everything about a team, so stage points contribute to all four actions. (1) They are acquired by killing enemy players and (2) "spent" immediately. (3) They are not ephemeral, (4) don't need to be transferrable, and (5) being permanent, are effectively limited by how much is available to spend them on (teams can only stage up twice).
It's notable that passive defense and passive offense both require resources in Tremulous (structure building is the only act of passive defense, and the free weapons don't offer any method of passive offense).
The questions for Unvanquished are:
How many resources should Unvanquished have?
What actions should they enable or empower?
How should they be acquired?
How should they be spent?
How ephemeral should they be?
How transferrable should they be?
How limited should they be?
*You could argue that it's passive to assist teammates in active offense and defense, but I think in team games it's more instructive to look at the actions of a team as a whole. An alien team in which one player kills enemy bases with a dragoon and has a basilisk buddy healing and disorienting humans is engaging in active offense, even if one "attacker" is only acting as a force multiplier.