Horwath
Legend
bards are little overtuned in spellcasting department.Statistically, chances are, there is going to be someone else with good charisma in the party. Frankly, sorcerers cannot be "S" tier so long as bards exist.
full casting might be too much for bards.
I would give them 2/3rd spellcasting, spells from 1st to 7th level.
but make spell secret default in their spellcasting.
Bards can pick spells from any spell list.
versatility is payed by not having access to 8th and 9th level spells and slower spell progression;
new spell levels at bard levels: 1,4,7,10,13,16,19.