Chad Mages What else would you want right now for our class

[Archwizard]

There’s really no need to be hostile.

Regardless, my point is that you've developed a system where your proposal only seems like the best option on the grounds that you've also simultaneously proposed nerfing every alternative into the ground first. Bearing in mind that adding more buttons is no smoother or more nuanced, nor does it necessarily net more damage since with such a grandiose restructuring, our potencies would have to be tuned around the changes anyway.

The reason we follow Freeze with hypothetically-actually-good B2 (before level 70) is that ice spells cost 0 MP in UI3 and we are starting with 0 MP. As you know, MP regen ticks are 3 seconds long, and it’s effectively random whether our GCD lines up with them. Best case, we get one immediately and can skip B2. But, worst case, one hits right before Flare resolves, and we sit there hammering our T2 button for 3 full seconds while our mana bar remains resolutely empty.
Good news, though - all our ice spells are free! So we can cast (long range, 80 potency) B2 and get some damage in. 240 potency over 2.5s beats 0 potency over 1.5s on average - you can plug it in to my numbers and see. And, in the real world, that average 1.5s of dead time is going to be even worse for us in relative terms because our GCD is probably shorter than 2.5s.

A difference of a half second is frankly nothing for "recovering", particularly when you consider your MP is continuing to grow in UI or out of phase, and the raw potency you'd be losing over it. You state that B2 would be worse than Freeze for that purpose, but there is no reason to nerf Freeze out of that position -- yet you seem resigned to it.

But I do admit that the need to wait for that first tick on some invisible timer is a (separate) lingering issue, one which affects our single-target as well, which could be resolved a multitude of ways -- those that give instant means to cast B4 and/or Thunder without clipping your MP recovery being chief among them, such as by having your transitional spell generate instant starter MP, or as Shurri has suggested before, just synching the MP tick timer with personal phase alignment rather than server ticks. At the going rate though, with Thundercloud procs drawing out AoE, we already have pretty consistent Polyglot charges every rotation which could at least buy time for MP; don't really need another spammable ice GCD to pace that rotation out, really just 1-2 GCDs in total (... such as the free transitional skill that Aspect Mastery claims we're due).

Flare’s ability to swap you into fire mode but leave you with mana is new, and it’s also clearly marginal and unintended

They literally feed us two separate traits at level 68 to make that possible, and it remains one of only 3 spells (with Despair) that gives AF3, so how can you say that's "clearly unintended"? If the devs wanted Flare to be purely a finisher move, they would have had it go the way of Despair long ago and barred its use during Umbral Ice -- and then we would never have noticed that Flare is the weird exception to nearly every phase-crossing nuance of our rotation.

Umbral Hearts are fundamentally designed to reduce Fire spell costs during Astral Fire, which is why you don't lose any for popping Fire 3 during UI phase -- but Flare is the sole exception to that, consuming them even in Umbral Ice.
Aspect Mastery is designed to remove the cost of transitioning between phases, which lets us squeeze that little more damage out of AF phase in single-target -- but Flare is the sole exception to that, too, continuing to have the same cost (even up to all of our MP) regardless.

If anything seems "clearly unintended," I would think it would be the lack of consistency in our core mechanics, particularly the ones they've added each expansion.

Ultimately, it’s lame to have to cast a mixture of weak, crappy flares and powerful, explosive flares.

And it's any less lame to be forced to cast the wet noodle that is Fire 2 at its absolute crappiest, for a job it already shares with two other spells?
Why do you think that level of redundancy and additional bloat would feel any better for the kit, than having us exclusively use our most powerful AoEs -- Flare, Freeze, Foul and T4 -- to call down disaster and do the jobs they do best?

And, even if we’re okay with watering down such an iconic spell’s identity, we still have the problem of a totally extraneous F2 on our bars because... [Flare]'s not STRICTLY better. It’s just... better. But if you need to deal AoE damage in excess of 100 potency in only 3 seconds, and want to stay in fire mode to be able to follow up immediately with a Flare or F4 or Despair on a different target or something, you can only do that with F2, not Flare.

Well in such a fictitious scenario that fits your oddly specific narrative, it's probably a DPS check which a good player would most likely have prepped Umbral Hearts or saved cooldowns for, including Swift/Triplecast and Manafont.
Unless you didn't mean that Flare is supposed to be a big, powerful add-finishing move after all? Since "we need adds dead, NOW" seems exactly the scenario Flare is made for in your mind?
Well, in that case -- and here's my favorite part! -- you could still get more potency out of Cold Flare than AF3'd Fire 2. Even with your upgrades.

That isn't at all the reason F2 is still on our bar, and you know it. For those of us who didn't throw it aside long ago, it only remains for the purposes of level syncing -- which goes back to my original suggestion of having it upgrade!

I do not know how else to say this to you:
It. Doesn't. Matter. If Flare consumes all your MP and Fire 2 doesn't.
So long as Flare amounts to at least a sidegrade, to the point of Fire 2's exclusion (such as, oh, the present reality), it could easily be treated as a functional upgrade -- there is zero rule imposed upon the devs that says every replaced ID needs to be a strict "X becomes X+1" bonus, and you literally showed Bio II as a precedent for such accepted behavior on their drawing board.

If I seemed hostile earlier, it's because to my eyes, the only one imposing such a narrow-minded limitation on the definition of "advancement" is you.