I doubt they could make something worse than armor lock if they tried
Their failed attempt at changing it would probably rank up there. Because the drain from damaging an AL user is so laughable that I will never waste grenades or sniper rounds trying to knock someone out.
Instead of trying to salvage an AA for modes it didn't work in, they should have just done like Bungie did previously in Halo 2 and Halo 3 and Reach matchmaking, and just delete the AAs from the MM lists they don't work in. At least there's a decent chance that the TU "fixes" will never soil Invasion, because the broken and bugged bleedthrough system would totally break the Elites. It'd be like playing with Blackeye on.
As it is, the AA changes felt like a tweak for the sake of a tweak and that time could have been spent fixing actual bugs, or adding a new menu option that lets you adjust Equipment Usage Drain as a percentage and let use tweak AAs ourselves.
They'll probably do that around the time they finally admit they can't separate bleedthrough from the other TU settings.
You know what would be nice? If you could update your current status on your active roster. Where instead of it saying "Homeboyd903 - Using the Forge," it could be changed to say "Testing a map. Need participants.".
Or instead of "Matchmaking - Searching" it could say "Searching in BTB with a party of 8.". I know some of this info is available if you view the party details, but I often don't want to check every persons status by going into those details. If there was a way to customize it that would appear on your active roster, it would be much more valuable. Perhaps even custom messages. I understand the problem that could create, but as we've witnessed many times before, you can already say whatever the hell you want in a PM anyways.
The way Bungie did that was to re-use the Rich Presence data in game. You'll notice if you pull up the guide, their presence will be the same thing (ie, GAMERTAG - Playing Halo Reach - Matchmaking - Searching", hence why sometimes if Live falls behind, you'll see someone in a party that says something like "Playing Free Bird on Expert Guitar" because Live is still reporting them playing RB3. It'd probably be up to MS to allow that to happen.