Draft according to your teams strength and weakness I would say.
Also keep a few capable players which is much more flexible to play the possible counter heroes of opponent's possible draft.
If you can't counter pick, then I would advise playing with what your team is most comfortable with since I always notice it is pretty difficult for certain players to switch they play style, e.g. from a farmer to an initiator.
Btw, I am not pro, still learning also.