3-stage toggle. "Off" / "Ask me" / "On"
Suggested that 7 months ago.

Somebody get this person a gold star! He thought of it first.
Like everything else that is good, it bears repeating so maybe Larian will do it.[
I also think some others suggested this months ago.
Ultimately, let's get rid of excess action buttons.
Toggle for Main Hand - switch to Off Hand. This designates which hand you default to when you hover over an enemy and the Attack icon appears. Click on enemy, attack with default hand first. Click again, attack with off hand (if 2 weapons equipped).
Special Attack Toggle - On/Ask/Off. Defaults to On so you usually use it on your first attack. Switch to Off so you can use it on whatever attack you want or Ask to interrupt attack as system asks if you want to use it on the attack and at what level. Works for ALL special attacks such as Sneak Attack, Maneuvers, Smites, etc.
Each character has their own toggles so you can handle each differently.
Get rid of Single Duel Toggle. You don't need it if all you have to do to attack with the off hand is just click on the enemy a second time. It takes literally a split second longer, but it gives the player full control over both attacks.