the descriptions is purely based on my experience and what I think okay? This from my point of view.
top 3 would be
-A hitter/support that I usually use as a hitter in a trilane she can also depend a lane on her own.
her skills arrow shot causes painful damage and can be handy when farming though, her shackle shot is a little tricky but once you get the hang of it you'll be able to use it easily. Her wind run gives her the speed she needs to capture an escaping opponent and can be use to escape when you get ganked. Her last skill on the other hand I don't use it that much. I prefer the attributes than her last skill :)
2. Crystal maiden
-crystal maiden is probably the best support for me she has frost nova to slow enemies and deals damage, She also has the frost bite which can disable an enemy and can cause a pretty good damage as well and her brilliance aura that makes me always want her as an ally it can give you a fast regenerating mana and it's global! and her last but not the least is her deadly freezing field. The only bad thing about crystal maiden is that she is very slow and has a low hp and defense and with her useful supporting skills thus making her the number one target when it comes to clash.
1. Queen of pain.
-queen of pain that's right! she's my girl :) she is my top pick or ace hero. I always use her when we have a money match (pustahan) and I always put her in the mid lane.. her venom strike slows a target while damaging it slowly.. It is a good combination with her blink thus making her deadly because she catch or escape as she please with her blinking skills. Also her scream of pain deals a lot of damage and enables her to kill creeps faster and then we have her last skill the sonic wave! it's very useful in clash and deals an enormous amount of damage :)
well there you go! here is my top 3 hero picks :) what's yours?