Has Raise Power been changed in the last 10 years or so? Last time I picked it up, I recall it being denigrated a lot as a guild spell, and I never picked it up again after the spell wipe. Has it gotten better? Is it useful now?
Its duration has increased in 2016, so it should last longer than you may remember. I still don't use it much personally though...the Harness symbiosis seems to provide a good enough boost to the mana available, and that travels with you. If you plan on staying put for a while and need more mana though, RP should serve quite well.
I never use it. Tanking fatigue is a huge pain even with refresh up. Instead, pick up an Aura Sight scroll. It's not the safest to cast, but you're an empath.