The dimple idea is horsesh-t, you screw up flow patterns based on the dimple pattern itself. I've seen dimpling done but it has to be precise and much aforethought given to it. True dimpling is not a low hole, rather a low next to a high, made by dinging soft aluminum at 45 degree angle with a rounded small point punch. The HIGHS then become the flow modifying force.
What's the difference between golf balls and head surface, the ball spins rapidly, your head does not (or maybe ONE of them does, anyway). When head does not move the pattern will take on significance..........
Don't use dremel, you gotta be crazy. I use dremel, a set of 35000 rpm big tool and die grinders, drill, files, whatever it takes to get part of the job done. Airtools suck, the hose is always in the way. I use rocks, carbide cutters, cartridge rolls and flapper wheels to do it. And lots of WD40 to keep cutters clean.
The most rewarding work is always in the first one inch of valve pocket even if rest of head is untouched, these seem to be pretty clean as compared to earlier American engines and probably not so much to gain there as 1turbofocus has mentioned here before.
I have seen more novice ported heads of all brands than I can count yet the ones that I thought might work better than stock I could count on one hand. The bad ones were proven out at the strip to be dogs. If you have no idea of portflowing then the odds are highly in favor of the fact that you will be screwing your head up if you touch it.