My opinion.
BARD - College of Eloquence
Undeniable Logic is too strong in my opinion. Completely renders Heightened spell metamagic obselete.
Infectious Inspiration should just give you the ability to inspire two allies at a time.
PALADIN - Oath of Heroism
Oath Spells. Replace Enthrall with Enlarge/Reduce.
Beyond that, I’d say it works fairly well as a Champion Fighter, in some sort of “only spellcasters permitted” game.
All in all, I think that this new round of UA PDFs is intended for the next 5e Magic the Gathering campaign guide.