Backseat Designer: Mass Effect 2's Ammo System

The Mass Effect RPG is hardly the only way these games have been bouncing around in my brain for the past several weeks. I've held off on posting this, because I couldn't find any kind of statement by the ME2 design team explaining their rationale for adding reloading and ammunition mechanics to the combat. I'd hate to have overlooked something while hashing out this proposed alternative. Happily, one of the slides from Christina Norman's recent GDC presentation lists what I'll assume were the primary factors:
-"Encouraged using different weapons" (Gives the combat more variety & tactical depth.)
-"We could make weapons more powerful with limited ammo" (I'm guessing she's referring to 'feel', though this also expands on the weapon-switching tactics. It's a shame they wound up treating new weapons like clear upgrades, rather than letting variables like this create more interesting choices when it comes to your weapon loadout.)
-"Stopped bullet spraying" (Shooter gameplay gets brainless very quickly when you're running low on reasons to worry about making each shot count.)

Other benefits I would name:
-Finding time to reload=tactical gameplay. The player's mental muscles get a better workout if their plan of action for the next 5 seconds has to account for the need to reload. It's a significant part of the shooter formula- look at the Call of Duty series, where the tutorials go out of their way to stress how the choice of when to reload also includes the option to switch to a sidearm.
-Maintains intensity. Waiting for your weapon to cool off was definitely a buzzkill in ME1. Most of ME2's improvements in this area come from the reworked controls, powers, defenses and enemy behavior; still, reloading also helps.
-Pushes the player to remain mobile during combat. Hang back during ME2's larger engagements, and you'll soon find yourself hungrily eying the pile of thermal clips beneath your enemies' feet. The option to shift positions so as to scoop up more thermal clips presents players with another dynamic challenge.
-Rewards exploration out of combat. This would be the one benefit this proposal would have to give up, though the level designers didn't really leverage it anyway: Some thermal clips could have been placed as hidden goodies, a lower-key version of the minerals and credits.

So what's going on in that youtube clip up above? Here's the details for my proposal.
-You always carry a small number of spare thermal clips. The exact number's obviously something playtests would determine; I'd envision having 2 at the start, 2 obtained by researching upgrades, and 2 more for those who equip spare ammo packs (or 'extra cooling units'). If we're hypothetically applying this to ME2, you could put the 'blueprints' in Mordin's recruitment mission and the disabled collector ship, with the armor upgrades on Omega and Tuchanka. There could also be several research upgrades providing small boosts to your clip's cooling rates.
-Eject a clip from a weapon and it'll start to cool off at a steady rate. You can't load a clip until it cools off completely. My initial playtest estimate would be 15 seconds for a fully-used clip to 'recharge'. I'd originally written out a lengthy explanation for how the GUI could convey all the relevant information in an intuitive fashion; then I remembered that I had access to a copy of After Effects, and could just show people what I was talking about. Something the above video doesn't demonstrate is that once a clip is fully cooled, it blinks white (with an appropriate audio cue) and loses the red aura.
-Clips inside your unequipped weapons also cool off, albeit at a slower rate. Regularly swapping weapons thus reduces your need to reload without making it irrelevant. The classes that spend more of their time shooting things are also the classes with the larger arsenals, so I think this could balance them out nicely. The fiction would be that a firearm's heat vents are open while it's in the 'folded' state. If I had to guess, I *think* it'd be best to still have a fully spent clip 'overheat' and not be usable until fully cooled (or until you eject it and load in a fresh one).
-Picking up a thermal clip swaps out your hottest spare clip for a cool one. Most enemies could still drop clips, and there'd still occasionally be one or two on the ground/shelf/convenient waist-high rock formation. You might also have the player stop and take half a second to pick up clips a la recent Resident Evil titles, just to add to the challenge a little.
-Bolt-action weapons like the Claymore and Mantis only expend about 1/3 of a clip, but 'overheat' with each shot. So you still have to reload (or swap weapons for a moment), but each clip cools off quickly. This is just a way to 'translate' these weapons so as to preserve their unique pros and cons (which are wonderful, the sort of thing that ME3 could expand on beautifully. I'd love to launch into a tangent on this topic, but it'd take up a post itself). The ammo capacity upgrades for shotguns and SMGs could translate in a similar fashion, altering the weapons so that their ejected clips are only half as hot.

One last set of bullet points- the advantages this proposal would give.
-Changes the mechanics to match the fiction. Mass Effect 2's in-game rationale for the use of cooling clips ties beautifully into the game's overarching plot while providing a simple, easy-to-grasp explanation for the mechanics. Yet people are still baffled, and not just because said explanation's tucked away in the codex. To quote Tom Francis: "That’s not how it works. You can run out of cooling clips for your pistol and still have 245 for your sub machinegun. There’s no way to use the pistol until you find more cooling clips for it: so weapons do have mututally exclusive clip types."
-Helps the IP regain a measure of the lost originality. This was the thing that made infinite ammo so cool in the first place- it was the setting's originality made manifest in the form of unique gameplay elements.
-Adds interesting tactical depth to the gameplay. As always, this is just theory. But keeping track of your total ammunition is more of a healthy play habit, with the interesting moment-to-moment challenge only really cropping up when your ammo runs low. This would help give players an engaging cognitive workout on more of an ongoing basis, with players planning out their actions so that all but one or two clips will be cooling at any given moment in time (so as to maximize their "enemy being shot in the face" rate).
-Reduces the workload for level designers. Rather than having to place a hundred thermal clips in every combat mission, they can plant a clip or two in the middle of most firefight arenas- or any other visible location that'd be interesting to try and advance towards while the bullets are flying, especially if it wouldn't normally be the smart/conservative thing to do.