Personally, I find that the commendation system is too 'broken' to take seriously. If they wanted to address that, it would need a drastic overhaul.

That said, I think it's not supposed to be taken seriously. It's a fun little extra added to the game.

I find that I get the most commendations on my DPS than my heals/tank now. Somehow in the expansion things just did a complete change for me. I also find that if I play 'really well' on my SCH, I am less likely to get commendations. i.e. If I DPS a lot and no one dies, 0 commendations. If 4 deaths happen and I just sit there mostly afk (not literally, but mentally, i.e. watching Netflix), but keep the tank topped up, then I'll get 2-3 commendations. I am not really sure why this is.