I think the whole idea of a buff SLA is a mistake. unless it is a short term powerful one. or they do something like wards 300 pts of damage.
Other classes SLA in T5 is something powerful that can be meta-d that is used in almost every battle, that closely matches the whole theme of the tree.
Shouldn't be a buff, shouldn’t be raise dead.
1) Should be a heal of some sort. Even if it’s a new one.
2) Generally a t5 SLA has a level 24? counter part Master of _______ that MCL get a boost as well
if not
Make it passive that as suggested makes turning based on WIS or extremely increases the HD to make it viable in Epics