The other team is even MORE likely to get a troll/feeder on their team than yours, since if you're a solid player there are only 4 possible trolls on your team, while there are 5 possible trolls on the other.
This is assuming, of course, that you aren't a feeder/troll yourself. If you truly are at 200+ elo above your current elo, then you should carry most games with absolutely no problem. It's like playing a lv 30 vs lv 1 newbs, even if your team sucks you should go like 20/0/15.
So if you are consistently playing at 900 elo, you probably belong there. Kills don't mean everything.