Yeah, keeping the food limit, keeping gold spent and using hotkeys. And maybe scouting. The rest is far less relevant. Compulsive micro-managers can generally be offset because they can't focus on everything at once, not to mention they can get tired (bigger strain on them than on you) or impatient. As someone with a fine motorics impairment in my dominant hand, I tend to rely on ranged units and/or buffing more heavily, as well as doing upgrades (which is a different way from micro of losing fewer units and it's passive) and having stuff properly hotkeyed (including sometimes the upgrades building of which I sometimes build two when I have good enough economy). Although, say, after years of playing Warcraft 3, I sometimes beat better macro/economy managers by sheer micro, but putting the same amount of time in it, a typical Korean kid would end up 10 times better than I am.
Generally, I've discovered that it pays to play stupid and try to deny the other player any advantage he might have or offset it (and the longer he underestimates you the better, e.g. for using low tier units and little variety) rather than trying to beat him at his own game. For example, don't prevent what he's doing to you, just do something nastier to him. If he's putting up a challenging micro match, just allow him his little show but prepare a strategic surprise. If he always manages to spam more units than you, then get some buffing/debuffing or, better still, make sure he's stuck with crappy units at a more advanced stage of the game.
Generally, don't try to match him in whatever he's doing, try something else. Even if you simply disorient him and change the situation for him, you will be foiling his plans and possibly making his cash investments go to waste. Sometimes it also pays to be decisive, even if randomly, just as long as you don't waste time picking targets, inflicting pure economic loss is still better than sitting around (although hitting strategic buildings to send him back to stone age is better still).
Hard to say more without having played SC2 yet. I'll have to get it finally, I'd just flunk a degree if I got it now.
