These are good points, but will be much better points if/when stats are made more potent.
1) Exaltation was essential before MP regen. Now it's helpful, but I haven't even used it since 1.6. My tanks goes Aegis Boon II >> Deflection- that's ~30 seconds of little-to-no damage. I spend this time with my weapon sheathed.
2) Higher MP adding to MP regen I like a lot. I'll probably take advantage of this when stats are adjusted. Honestly, I'm hoping they raise MP costs, or slow regen or something...to me, MP management was between good & tough before, and now it's a joke- I can't spend it as fast as I can get it back.
3) They do all have their pools, but I've never seen one emptied in 3-5mins. An aoe siphon1 on Dodore's Minions will get me 700+ (which for me is like 80% of my pool). My LS kills Dodore in 6-8 minutes right now, and I haven't had a siphon fail yet.
In XI I used the Light Staff because MP management was pretty delicate, and efficiency was necessary, worthwhile & rewarded. The cure potency was a big help.
In XIV the cure potency helps efficiency, but it's almost harder to be inefficient than not. I'll always want more MP, but when I can siphon for an entire pool, or just put my weapon away for 20 seconds and regain almost 200 MP, I'd rather just add those stats to my INT/damage or PIEcuracy, but since PIE/INT seem to be pretty ineffective after 80-90... I just default to MND/VIT---mainly VIT.
I want to maximize my effectiveness, be the best that I can at my class, but when returns are so curved/diminished, it doesn't (to me) feel rewarding, and my group doesn't really benefit.
I'm coming to the realization that I can't make a post in this thread without it turning into a "change the stat formulas" rant--I'm gonna stop here.
Great Buffalo, Uraeus can't be siphoned. Easy enough to grab crabs/toads/squirrels/doe.
Dodore's Minions can all be siphoned and they stay in the spot where they die even after Dodore dies (assuming you kill him first), so you can AOE siphon minions for 600-700+ MP.
Hotpockets' Bouncers have some MP- when it runs out, just siphon lemur/ladybug/whatever's around.