Frumple, the thing is Dominion doesn't care about numbers. The only thing they're good at, is allowing bad players excuses, since it's possible that the worst player has highest score. Points - the rightmost yellow points players are ranked by, are gained by capturing and holding areas on the map, and I personally almost always let my teammates capture as I move to another objective, or to gank, or anything, which results in me having less points. It's really unlike SR, since turnarounds are easier if teams get organised. And yeah, 5 revives are pretty much mandatory in higher elo games, unless people are really good and know how to heal/ignite. Flash is absolutely useless, for example. And yeah, Dominion games end when your Nexus's health is reduced to 0 - the red and green numbers top. Health starts at 500 and starts dropping when the enemies are holding more points on the map than you.
We lost because suddenly my team started forcing engages in the jungle, one-man-armying and all-around retarding. It was mildly hilarious because I was sure we were winning this one and suddenly... we weren't. And every single game I lost in that six-game streak was like this. I had best score, did all I could, and losses kept piling on.
And Cthulhu, I play Dominion because it's more action-y and pvp-y. I should probably try the new 3v3, but I'm kind of tired of pve. Also my pc lags on SR, so there's that too. And yes, it's even sadder because I'm quite sure I'm above 1900 Elo right now and people are STILL completely ignorant of anything except chasing. Got a good 5win streak and BOOM - another game back in retardland. Going to stop now, since it's 3:30 a.m. and because I'm completely exhausted.
If anyone is just starting Dominion, my advice is, make sure every team has a Jax, a Kass, a Malphite/Blitzcrank, an Ezreal, and a Malzahar/Yorick bot, in this order. I'm pretty sure Jax bot also will wreck every low-elo game, because he crushes 1v1 and then roams off to kill the entire enemy team. This is the worst part about Dominion, since there are champions which are more or less broken. Oh well, I'm pretty sure Dominion is also getting looked at, and maybe we'll get a Twisted Treeline-like remake.