ive gotten pretty good at executing a perfect 7 pool. i usually rush till it looses its effectiveness, then switch up to either hydras, mutas, corruptors and broodlords (i usually send them in half and half, and once air units are handled i morph the other corruptors near the base im attacking), or some combination of them. i usually do well in equally matched games.
i also play protoss, but im really horrible at terran. i dont thing ive won a single game as terran yet.
i dont use cheese tactics with protoss. your better off building defences and/or units asap. but the thing about rushing is that after 2 or 3 waves, you need to stop and move to bigger units. you can work on your base while your zerglings are on their way to the target. i usually use the following build order in my typical 7pool:
drone
pool
drone
overlord
6zerglings
queen
2 drones
usually around this time my zerglings have gotten to the target (i send em off as soon as they hatch). next factor in a successful rush is finding an easy target. the closest base is your best bet to catch off guard. if i encounter a wall i usually skip to the next ramp. if theres noone shooting at you and you got some zergling teammates who are also rushing you can try to break down the wall. and focus on supply depots, attacking terran workers is very hazardous to the health of a zergling. protoss however have very easy workers to kill, and thats what you target, then hit pylons. if you encounter resistance at all bases, your best bet is to run the zerglings around to scout, killing targets of opportunity (lone zelots, marines, and workers), then immediately move up to advanced units.
thing is when youre at the end of the rush, its the time when your terran and protoss teammates (and zerg players who chose not to rush) begin their initial attacks. if you did your job right, the enemy should have fewer units and weaker perimeters. there should be enough going on at this point to distract everyone from what youre doing. you need to build up youre base and workers, expand if possible. if i need units asap i usually go with hydras, but if im in a good spot, and i havent been discovered, il put in the spire and go with mutas or push for brood lords and corruptors.