for zerg: Flanking possibilitys, ramps at expansion (placing lurx vs rines), minerals muta-harrassable,
for toss: flanking room, some cliffs(carrier), easy 3. expo (easy minsonly helps p far more than z/t), island expansions, easy defendable nat
for terran: tight parts, chokes, cliffs at expansions, easy defendable 3. expo (with gas),holes in the mineralformations, lots highground/lowground switches
I'll write an essay on balance after I shower and eat. It will be fucking long as fuck.
I assume however that you're just doing this to 1. Make me write a lot and 2. Make fun of me for my theory craft stuff and 3. Piss me off, etc.
If not, then oops my bad. But I'll write anyway.
Please bare in mind that I am a zerg player, and my understanding of sc is best with zerg, in zvt and zvp. I therefore sort of understand pvz and tvz. I don't know tvp very well at all. I don't know tvt at all. MY pvp knowledge is lax too.
I am not a progamer. I am not infallible, don't take absolutely everything I say as fact. What I will say comes from playing starcraft, from experience and whatnot. I'll post in parts, it's impossible to remember everything at once lol, sc is just too complicated.