Make sure that it is comfortable in your hand before worrying about anything else. Personal preference is going to ultimately be the deciding factor, but I like to have some heft to my mouse. I also don’t think that having a million programmable buttons is always for the better. I like the Logitech G502, which is weight tunable. If you do want more programmable buttons, the Naga Razer is nice if you can get one that works properly, but they seem to have more than their fair share of issues and I think it’s a bit of overkill for Dota 2.