Experience is important.. to a degree. Map objectives are always priority though, the only exceptions are pretty niche: on cursed hollow, you can sacrifice a tribute that WONT curse your team, if the enemy is already lvl 10 and you aren't. You'll want to soak exp to catch up before the next tribute so you'll have heroics as well. Things like that is really the only exception
Just had a game with a player who afked FIVE times, quit mid game, came back later and afked again. I check his match history in his profile and he loses like 80% of his games... why the fuck would i get paired with people who should be permanently banned for this behaviour?
These people have tanked my MMR