I know this has been discussed many times over, but as I'm thinking of playing a monk of the four elements soon I was thinking what I would change if I was the archmage of the coast.
I would change one thing aboit monk of the four elements. A single thing. I would at third level allow them to use a ki point to cast absorb elements as a reaction.
I love the idea of absorbing an elemental spell cast and them and using it straight after in a strike. It has a very deflect arrows feel to me.
In your opinions, would this make the subclass more interesting to you?
I think it's a cool and appropriate concept but it does nothing to adress (if anything it only worsens) the main issue with WotFE; it's abyssmal recource economy and scaling.
You could change it to something along the lines of "1x per long rest you can absorb the effects of an elemental spell to restore you Ki points to full" and you'd still be fine.
I don't think that's true at all, actually. Paying 1 ki to cast Absorb Elements is in line with how the Shadow Monk functions. It's a totally fair price that enhances the strength to the class overall. It doesn't fix the subclass, but it certainly doesn't make it even worse. Combine it with reduced Ki cost of all disciplines, and 1 cantrip per subclass level, and you've got a subclass that wouldn't have been viewed as outside the normal power band of the PHB as a whole.
However, there is room for a bit more, and it could work more simply.
First, I'd give the subclass the wu jen disciplines from the UA mystic, gaining 1 for free at level 3, and fold the effects of the elemental evil utility cantrips into the appropriate disciplines.
Second, I'd add at level 3 an ability to absorb elemental damage as a reaction, reducing it by half. If you spend 1 or more ki, you can deal 1 or more martial arts die of that type of damage on your next successful melee attack before the end of your next turn.
At level 6, I'd add the ability to make all of your attacks deal the elemental damage of your currently active wu jen discipline (renamed, obviously) when you use Flurry of Blows.
Later, I'd maybe look at upgrading the level 6 ability to that your attacks can always deal elemental damage, and you deal extra damage of that type equal to your proficiency mod on all attacks when you Flurry? Or, maybe your late level benefit is choosing a lower level discipline with a casting time of 1 action that you can now cast as a bonus action?
The level 3 and 6 benefits are the most important things, though.
Then, the rest would remain that same, except that disciplines would cost 1 ki per spell level, instead of 1+1/spell level.