As I know the first Starboard center from north is http://www.europasurfandsail.com/
in Malcesine, that mean good for strong north winds in early morning, not so good for the afternoon Ora from south. With Ora the more south you go from Torbole, the lighter the wind become.
Northern part of Garda lake can be crowdy (I mean in the water) with sometime 500 windsurfs planning togheter in the two directions (so crossings...), but imho remains one of the most breathtaking places of the world for our sport (Think at flying straight in the direction o a 300-400 meters wall of rock, Ponale, sorrounded by mountains, in spring also with snow cap...).
Please consider anyway that Ora and Peler are thermal winds, so bad wheater and other factors can block the wind. Anyway you're in a spot full of alternatives in sport but also for visiting historical monuments and enjoying ....italian restaurants (try Teroldego red wine and "strozzapreti" pasta - in italian sounds like "priests-suffocating"...)
Hope can help