My issue with both of your creations is they seem to be trying to do everything and have way too much going on.

For Azusamo, I don't get why something aggressive that is dealing damage every turn would need a way to dump its hand extra fast at 6 mana. At 6 mana, you're either a lot more controlling or it's just not being cast. Only time I could see that as useful is in a stompy style commander deck, but even so...

Ignoring that you didn't include a P/T on Exavalos, putting mana generation on a creature that otherwise screams pure aggression seems very strange. Sure, they're cool abilities and reasonably synergistic, but it confuses the purpose of the card. If you want to make multifunctional cards, give them a clean, single ability that does that, not just slap a bunch of different abilities on a single card. Finally, Jund doesn't distribute it's +1/+1 counters. Black and red are purely selfish, and the part of green that shares counters is much closer to white color pie wise.