All heroes in the pic (except TT) got their skill at 8,can take 3 heroes to 10, ty in advance for your suggestions.
First pick heroes You are using most, since they will benefit most.
As fo my pick, i would use Anubis, Walla, and Sasq.
Anubis for more power, and damage reduction,
Walla for better healing, but also more healing targets at skill lvl 11,
Sasq, for 0.9 sec freeze, which is basically like freezing for 5 secs. Additinally you cal lvl up his skill to 11, which will decrease cooldown by 1 sec..
But like i wrote in first place, pick heroes you are using most. There is no point in lvling hero, which you are using occasionally.