I like the LFD tool, but to me the bonuses they give you just dumb it down a lot. But I get your point that there are a lot of bad players and you don't want to waste your time in queue ( I remember cata heroics near launch lol). I think WoW is trying at least to please raiders and casuals at the same time. Hardcore guys got mythics, the casuals got LFR.
I would make silver proving grounds a little tougher though, add in moving out of aoe situations for all specs so you keep the really bad players doing normals. Keep the noobs out of heroics.
My issue with CRZ is that you end up competing for quests with a bunch of randoms from random servers. Now this is the same as the LFD tool but to me LFD tool saves a whole lot of time so I find it ok. But zones don't save me any time. They populate my low pop zone with 15 other guys trying to loot the 8 boxes... I remember back in the day when you compete for quests, you group up, you make friends, you quest with them the next day and its great. You don't do that nowadays. Heck I even find it weird when 90% of my guild is from the linked server. If there were still big elite quests you had to group for I could tolerate crz, but heirlooms = lawlz.