Agh so many heroes so many choices. It's fair to say I've played roughly half of them by randoming it up, and that's probably a generous estimate. Can't quite decide wich one to practice and improve with. Harder still when nearly every match is incredibly lopsided so I can't tell if I did better with one in particular or matchmaker granted a sure victory/defeat. In fact the matchmaker doesn't seem to stellar so far, almost always one or two of skilled players preying on clueless newbs.
But back on topic. I don't know are there any heroes that are plain bad? There's lots of them so I'm sure there'll be a few that just flat out suck and I'd want to steer clear of. Likewise heroes that are simply overpowered aren't interesting either, I prefer a fair competition above all. Not a huge fan of nuking either. Of the ones I played here's some I enjoyed: centaur warrunner, bristleback, slardar, naga siren, rubick. Still got quite a few to try out of course.
Also on the topic of balance, is it just me or are shadow shaman and witch doctor immensly overpowered? As in will disable and destroy your entire team before you can blink. Just lost a 5v3 where the two of them just wrecked all five of us soon as we so much as came in range. Couldn't believe my eyes when I saw the damage the two of them together were dishing out, they could probably have won it 2v5.