Ideas:

Destruction of the Temple makes nuclear launches impossible - since that's all it was good for really in the RTS (but GDI should be able to keep buying beacons, since the ION is space-based and not fixed like the Temple is - kinda evens the playing field a tad, but lamers would complain - even though it would have been their fault for its destruction to begin with, because if it were destroyed, that means you either 1) let armor DEEP into your base, or 2) allowed more than one Hotwire to get into it.

Destruction invalidates "advanced" units, like the useless stealth tanks and "invisible men," yet keeps units like Raveshaw, Mendoza, and Sakura, since they're unique. A temple should also make "tiberium advanced" units - like the Templars, purchasable units instead of "easter eggs," as a NOD "Patch-equivalent" would be useful.

The Comm Center is a cool idea, but it's a game imbalancer - rather, a better idea IMHO would be a sniper looking into a base with his rifle (supposedly equipped with a high-gain microphone), should be able to listen and relay the messages back to friendly forces - but give it a definite range, otherwise you'll have everyone buying Deadeyes and Havocs trying to be snoops and there'll be no one to defend.

I'm also thinking that a damaged power plant - down to yellow, should reduce the range of the Ob shot by 1/2. Because if a team allows a plant to get that low to begin with they DESERVE to lose 1/2 their range on the Ob. It'd also give GDI an edge, but the same would have to go for them as well. A flame rush getting 1/2 more distance to the base before getting fired on would be lethal, and give people a better incentive besides their units becoming 2x more expensive to set up passive defenses.

I'm also wondering how an SSM launcher (which wasn't an original commandable unit - along with the stupid Chameleon tank) could work and what the "reload" time would be. Quite frankly, I think they'd be useless - but if WW plans on making a RA Renegade, they have to figure out something...

SAM sites are a good idea, but a better one is to put a "locking" feature on rocket soldiers. It'd force some people to go anti-tank, and in the process they become lethal anti-air weapons as well as much more effective anti-tank troops. But then you'd have to make it so it doesn't lock onto infantry...and also make sure to keep the MLRSes rockets unguided, as they are in real life.

Visceroids. I mean, they'd be great dual enemy weapons - as they'd attack anything, and spice things up for both sides. Imagine a flame or armor rush going through a tib. field and getting chewed up a little by a few "indigenous" lifeforms.

That's all I can think of for now.