What's this recover skill you've mentioned?
I thought u mean restore, which last for 18sec with 5 sec cool down...
Do u mean invincible?? 5 skill point into cool down for invinible will reduce the cool down by 5.4sec...
I cant say what u should and shouldnt empower, it's been discussed in many other threads...
but i thought i'd show u this:
http://www.fiestafan.com/wiki/Cleric_Skills#Invincible
This may help u decide how you want to use ur points wisely...