Hussar
Legend
Oh, sure, an all caster party at those levels could be a possibility too. I just find that it's not a likely one.
As far as class optimization goes, I'm afraid that it mostly takes a back seat to the big ones of higher point buy value and humanoid opponents. Going 35 point buy value boosts your character a full level in every meaningful way - hit points, attack bonuses, damage bonuses, bonus spells etc. And humanoid opponents are usually very weak compared to similar CR'd monsters. Anywhere from the weak end of the CR to one or even two CR's lower.
That's where I'd lay my money.
As far as class optimization goes, I'm afraid that it mostly takes a back seat to the big ones of higher point buy value and humanoid opponents. Going 35 point buy value boosts your character a full level in every meaningful way - hit points, attack bonuses, damage bonuses, bonus spells etc. And humanoid opponents are usually very weak compared to similar CR'd monsters. Anywhere from the weak end of the CR to one or even two CR's lower.
That's where I'd lay my money.