Xeviat
Dungeon Mistress, she/her
With extra attack 1d8+1d8+1d4 is better than 1d6+1d6+1d6, also AoO's are better at 1d8 vs 1d6.
Also, I agree that Dual wielder feat is bad. If it were "half-feat" that would be good.
But most of the TWF issues would be solved with off hand attack being part of the attack action.
OH, sorry, I meant as part of my alterations. Yes, Rapier/dagger would be better than duel shortswords in the standard rules with Extra Attack. I advocate for no ability modifier to off-hand unless attacks are split, and equal off-hand and main-hand attacks. I'm still waffling on if I think the bonus action should be required; because of the rogue, I believe it should be required, or else TWFing becomes the defacto rogue melee style (My fix for that is to offer a +2 attack bonus if you attack with a one-handed weapon and have an empty off-hand, which helps boost sneak attack damage to be more equal with a single rapier as two shortswords).