Can somebody give me some “reactive” builds for wehr and usf

I am gold/silver player and so far I only played build that rely on the specific battlegroup, like I chose luftwafe at beginning because I gona need air drop at stuff like that. I found it working pretty well if built is versatile enough it can counter anything oponent decids to do, but I was wondering what it be like to play build that can work with multiple batlegroups and you chose it during match to adapt to opponents moves. do you have builds like that for wehr and usf those are factions I main. Basically what is game plan and when you chose battlegroup and how you use it with the build