Hi, local gray mage here!
Enjoying time powers for the most part, but I'm not sure I really feel very 'useful' as a practiced gray mage, outside of combat and sigils.
The main concern here, is how easy it is to get timestrained when casting focus, which works better when cast repetitively. For those that don't know and don't mind knowing. Casting any gray magic seems to inflict a stacking debuff that makes it harder and harder to cast gray magic. From testing it takes 2 real hours for the debuff to wear off.
A fully charged clouded crystal will restore about 7 mind per cast at a cost of 4 mind per cast. It takes about 108 mind to get there assuming the crystal never fails being charged. This means it takes about 36 casts for a clouded crystal to start restoring more mind than it cost to charge it. Now, this still feels relatively fair. You're banking mind to restore later. and in a pinch. But you'll probably be too time strained about 30 casts to really keep restoring more mind.
Except, that really isn't worth it when you're trying to help people craft or scrounge. In the grand scheme of things, restoring 210 mind to a crafter or a scrounger isn't all that much. That's 42 active scrounge actions, 210 tiles of passive scrounging, or about 26 crafts for a lot of professions. (Like setting 26 stones by an oven.)
Naturally, better crystals let you restore more mind. But if this follows a similar progression to other spells, I believe it'll be about 17-20 mind per cast, as I've yet to be able to use a prismatic to test this... To fully charge a prismatic, barring the greater risk of breaking it at some point.. That's 300 mind (+ however many failures). At 20 mind per cast that's a net gain for 16 mind each time. Meaning about 20 casts to have refunded the mind it took. And now you're also pretty time strained, heavily increasing the chance of just breaking your crystal as you fail more and more to cast focus. At the same 30 successful casts, that's 600 mind. It's a lot better, except the risk of a prismatic under 30, fail-chance boosted casts.
On the other hand, succeeding in 10 casts in combat is then too strong. Giving an orange mage an extra 12-16 casts of lightning bolt in a couple of seconds, turning 40 of my own mind into a whole bunch of pain. Which in turn can trivialize some combat situations.
I admit, I don't know exact numbers, so a lot of this is still theory crafting. But even with a generous 20 mind per cast I don't see myself using this spell to help critters who sometimes need 1000's of units of mind to scrounge or fireset, at least not with prismatics or clears, they're too valuable in comparison to the time saved. When I can make a lot more money off of one very extended gray, yellow or blue sigil. Or by giving a fellow mage boosts in combat.
Instead, to make focus more balanced in both cases (combat & crafting, or even helping mages charge their crystals), wouldn't a longer cooldown to spells after cast be more balanced whilst making this one the only gray magic spell not to be affected by time strain? (As I do think it's completely needed for the others, especially timewalk to be affected.) This would make having a gray mage to get through crafting faster more useful. Focus could also increase mind regeneration a tiny bit for mere seconds, as a non extendable benefit, to make the mind-to-mind ratio a little better when manually charging crystals.
