Merc STR - Super fast , normal win ratio %80-90
Merc Focus - Slow , good win ratio %85-90
BH STR - Fast , good win ratio %85-90
BH Focus - Slow , High win Ratio %88-93
Mage - Slow ,Normal win Ratio (the thing is they need to make their dex +80 and use DM they will win STR builds but they r slow and not high win rate) %80-85
That entire list is a bit biased and.
Focus builds are not slow, they about a 2-3 turn win rate depending on what you have (bunker/bot/cheapshot)
Merc str. builds do not have a 90 percent win rate, and never will. Further more, since win rates are completely dependent on how many non varuim cookie cutter builds you can squash in 2 turn's before someone with some sense a few dollars comes along and nerfs/stuns/blocks you into submission, I'd say any build can have a 90 percent win rate. Exept str. mercs, which depend way to much on luck to be of any use at all I find. At most. I'd say you an achieve a 75 percent win rate with a str. merc, seeing as how half the game is a shadow arts bounty or 5 focus merc atm.Focus builds will slaughter most any type of str. build, but only if they invest in a few defensive moves.
Secondly, a malf/plasma/overload build is pretty much a 2/3 turn kill on most incompetent players, and even a few varuims with some luck. A support/5 focus mage build is very capable of a 90 percent win rate, there are many non varuim mages using this right now.
Way to many people think of caster builds as crap nowadays, which is a little disappointing when theres so much untapped creativity to use. I'm not saying max plasma/overload will be godly, but a nice mix of the 6 staff only skills leads to a very potent all around build, IMO.