ARAM only accounts ruining the game.

I don't know if its just me, but I am having a real hard time enjoying aram anymore. For me it was a mode to hop in real quick play a game or two and then get back to something else.

Now it seems every time I queue the team comps are wildly out of balance. If I get a good team comp 75% of the time someone on the other side dodges because 'they rolled the bad teamcomp'

When I do get into a game it usually consists of cancer champs like lux,veig,ziggs etc all while spamming barrier.

Why can't we just unlock all champs for ARAM? It seems like the only logical way to get a 'true' random system with re-rolls working as intended?