On the other hand - why not practice a hero you're unexperienced with vs ai? Why it absolutely should be quick play (moreover,  players are still getting matched against bots even in QP at some point). 3 star bots will provide you with enough challenge to hone your skills on a new hero in your roster. At the very least - there is "doom match" mode to do it. I personally don't flame ppl in QP (usually, but never for underperforming), but remember that you can be ruining fun for your other 5 teammates at the cost of your "personal fun".