I never commend dps for doing damage, just like i never commend tanks for tanking well, or healers for healing well. Commending a dps for damage is like saying "you did the job you signed up for, here's a reward."

I commend players for being fun. If you're chatty or telling jokes or explaining mechanics to the new person while also doing what you're supposed to be doing, then you get a comm from me. If no ones fun or engaging, then no one gets the commendation.

I don't come across situations where a dps rez saves the party very often so honestly maybe my perspective is skewed, but honestly, commending the red mage for raising a healer just, again, seems like a "good job for coming on a job that has a rez." That's something you should already be doing, its not really going above and beyond.