Well.... stam, crit, and SP along with res are the stats you need to be looking at, but as far as stacking them in order that's pretty tough. It depends on your team make up and size you like to play on. If your doing lots of 2s then stam is pretty important. If your doing 5s then crit is important since you get to heal a extra person with every crit.
If your talking about gems then put +res in your yellow sockets. For blue go with green crit/stam gems. For red go with purple stam/sp gems.
You really need to be prepared for everything. If your teammate is being focused then you need the SP and crit to heal him, if you are you need the res and stam to stay alive, and you never know what the other team is going to do.