I have been grinding PvP straight for about 80-100 hours. I went from a 0.65 to a 0.95 (with a max of 0.97). I was just demoted to silver and I am done. Whoever made the PvP comp system is either an idiot or just someone -blam!- hates fun. Get a win? +50 points. Lose because you played against some flawless emblem BS same clan sweaty goobers? -200 points! Also in what universe is relegation a good idea, I've literally never seen it in another game and it sucks and is super demotivating. Did I also mention, the only reason I'm doing this is to just get to plat, because I want the glorious title. That's it. No ascendent or anything like that, and that's usually when I've seen people complain about it. Now I get it, it's partially a skill issue on my part but that doesn't mean it still isn't super demotivating and made terribly. I have about 535 hours in warframe and not once was there a grind as bad as this.
Also rift doesn't feel like a competitive mode and just really shouldn't be in the playlist.