Bloodlust Horde does get much better at 80, and 70-79 totally depends on what day / time you're playing to how well you do. Ruin is just terrible all the time, but it may have gotten better, I haven't actively BG'd there in 10+ months.

Your que times in Bloodlust horde, only get worse. 10 minutes is normal where you're lucky to get anything under 7 minutes and you feel GRATEFUL when a 12 min que pops because it wasn't a 20 min. But the 15+ mins are pretty rare.