Emphasis on WC3-4, with WC1-2 warships as icing on the cake. WCP models already have good textures and all of that stuff, plus a really great engine already.
WC1-2 stuff is icing on the cake because Standoff is really focusing on WC1-2 stuff with a plot that involves WC2 vessels and such, It's "ethics" to not step on their boundaries and let them cover the WC1-2 era. That way, you'll actually complement their work with WC3-4 instead of being in direct competition.
Also, if you add WCP, you'll have to add all the alien fighters, all their taunts, all the music and weapons from that game. Plus the logistics of trying to find out what's the *true* stats of the capships (in WCP, they didn't *blowup* persay, they just sat there and explode).