Reliability I say that should stay since it shows if the person avg rate for showing up for these battles.
But it doesn't. If you show up for a battle and the other side doesn't show; you take a reliability hit. I was at 10 and had this happened to me several times (I'm at like 7 now) so I quit applying for smaller battles. The AI uses this against you when applying for the AI side of the battle.
I did miss one battle, actually I showed up late and kept getting kicked each time I tried to sign in, and there was a valid IRL reason.
Performance sucks too. I was running a 8 and had one bad series where I thought it would be cute if I fought melee style w/any weapon I found (me being an archer w/ no melee wpf), included in this bad day was a spawn raping at Jelbegi castle. In total I went 26:59 and the performance dropped to 5.