Finally got my network sorted out. Comcast's wonderful service was delivering me a quality 33% packet loss rate (seriously), which is what was resulting in me being kicked constantly. Got that sorted out (and because they're sneaky bastards who don't notify you of cheaper-but-better plans until you ask about them, $50 off our service package), so now I'm able to play Halo 5 again.
First match was Slayer. Did fine against the enemy team, but I got paired up with the no-thumbs brigade, so the average enemy team stomped my teammates and won with a sound "my whole team ragequit while the score was 12-30". First time in a long time that I actually left a match. I hate having to do that, but when three teammates leave, what choice do I have? Not a fan of being penalized for that, either.
Second match was Assault. Much more fun. Would've won much sooner had an idiot teammate not deliberately TK'd me while I was a half-second from arming the bomb, but I digress.
It's good to be back.