Concept for a Magic Melee DPS

[Archwizard]

It wouldn't compete for raid spots with Red Mage but what it would do is guarantee that RDM's melee abilities will never be expanded upon. It would also be far stronger overall and steal players away from RDM who want a spellsword type class.

Ignoring the hyperbole of "guaranteeing" a lack of expansion to RDM's melee, since expanding any other melee (including NIN and SAM who are the closest we have to Spellblades now) has no bearing on RDM's own kit or balance:

I don't see the problem with that. Every GCD we spend performing melee skills is built by anywhere from 2-8 GCDs spent casting, yet there are more requests for new melee skills or Mana spenders than there are for ways to generate Mana quickly to shorten our casting time.
I don't see a need for a Magic Ranged DPS job with "Mage" in the name, with a spellcaster's stats and survivability, and a repertoire largely of spells, to spend more time locked into melee range or see much more expansion of its melee abilities, at least not before its spellcasting abilities so we can spend more time meleeing.
Give players who want to live the Spellblade fantasy the option to live that out, and leave RDM for players who prefer the mixed-caster fantasy of RDM. Let players play what they want to play, don't hold the Spellblades ransom to RDM.

Also worth mentioning, there is hardly any discussion of how Spellblade would even work, yet you're already declaring it would step on RDM's toes? Spellblade, Mystic Knight and Rune Fencer are different enough jobs from RDM that there are plenty of skills and abilities that could be given to them that have nothing to do with RDM. We have no job capable of casting En-spells, FF13 gave us a whole host of elemental strike skills, FF15 gave us Warp Strikes, and there are plenty of ways to expand on a melee job that don't involve giving them a Mana gauge.
We're no more the sole owners of sword magic than WHM is the owner of healing magic.

Paired up with the curse of verraise, RDM risks becoming essentially a dead job.

Funny. I was having a chat with a friend about that last night, and it was pointed out to me that the Verraise tax was hardly a consideration towards the end of Stormblood, and a large part of the discussion around the Verraise tax cropped up when Shadowbringers launch made clear that BLM was overpowered.

Have we had recent dev confirmation that RDM is so undertuned right now because of Verraise? 'Cuz our damage was just as bad at the start of Shadowbringers before our casting costs were adjusted when we could barely squeeze out 2 Verraises a fight, and we were still behind SMN in utility.
I'd wait for 5.1 before discussing if Verraise is still a 'curse', versus balance having a few oversights.

I'm in for most class ideas, really.

But if any job gets Ultima or Ultima-esque abilities before Black Mage does then I will RIOT.

Bold of you to assume anyone will get Ultima within the lifespan of 14.