If there's one thing MoP deserves praise for, it's its content cycle. MoP was supported very, very well with good patch content at a very good cadence. The music also deserves huge props.

I admit, I played very little of MoP, and that holds true for any expansion in the post LFR age of WoW. I consider everything after Cataclysm to be "modern" WoW, and I can't enjoy it the way I do the stuff that precedes it. As far as "modern" WoW expansions go though, MoP is solid.