First, name the map then tell us your strategy.
I'm newb now so I do not play terrace anymore and have forgotten my reg map strats.
On Giant's of war 8 player (As GDI) I build one ref then after the war factory is up I build 2 apcs to send in to scout before building an extra harv then build 2 extra jj's to scout just in case the apcs do not work. Then, I tech up and dizzy you. After building 5 dizzys, I usually build up on bombers, titans and a couple of more refs then get my firestorm ready and begin expanding with an extra MCV, more helipads and war factories if I make it that far(Sometimes I do not worry about getting firestorm). I know it seems like kind of a strange strat but you might be surprised how often it works.
I am a little high right now so forgive me if I have fed the trolls.
I love it when giants get played with lots of GDI. It makes it more fun. I'm always GDI on Giants, just cuz me too, dont like the way its modded. I mean its great if you don't like dying and don't wanna learn. other then that I love to rush with GDI on giants as well! I don't really like your strategy to be honest, let me tell you mine:
when the loadscreen ends, im already pressing E+D with index and middle finger like crazy, while im doing that Im already clicking like a maniac on powerplant, get my screen in the position to place it as fast as i can, clicking barracks as fast as i can. I build my buildings like this the entire game, but mostly during start cuz i always wanna rush. I just build a few infs (if in back) to save money, 1 ref, radar, build JJ as fast as i can and order it to fly as fast as i can, 50/50 of times i fly through more then 1 base, I ALT my warfactory on the tib while i make 2 harvs right after building it, so i have time to make jj's dodge sams, i also Shift+F9 my First target's base so i dont have to scroll. I make an mk2 as fast as i can, selling depot,radar,tech right after i don't need them anymore. I build second ref, ghost, apc and another carryall, they might go slower cuz of low money, build while im doing this, my mk2 is killing all sams, all rocket man and threats to clear the way for the ghost. As my screen camera goes from home (H) to enemy base (F9), I team the ghost #1 and carryall #2, for easy controll of units. Hopefully i destroyed the base real quick and can move on to the next base, hopefully game finishes real quick. If it all fails im just hoping i will die quick cuz i hate long ass giant games.