I would rather prefer more classes for the EA and focus on base mechanics. The way the game works now makes me warry of playing it further as the balance/action economy is already questionable.
I agree but we really need level 5 as well for the 3rd levels spells.
Mechanics are important. Right now the Abjurer's mechanics are so messed up that it is not worth playing. (Arcane Ward is NOT temp HP).
Follow that up with Fireball being the wizard's power curve jump at level 5. And look at the Abjurer getting access to their key spells for counterspell and display magic.
I think level 5 is one of the most import levels to look at for everything you said.
