Gift of Gab wouldn't be too hard I think.
Just in the current UI, similar to how you can add bonuses, have a box that possesses the things that may allow you to reroll, such as Lucky Feat, Halfling's Luck, and in this case allows you to spend a spell slot to reroll a Charisma check in a conversation using Gift of Gab.
And for Reactions and Smite, I would prefer a popup, but perhaps allowing us to have the type of reaction "prepped" would be a good way for players to control what popups happen because some may have Hellish Rebuke because Tiefling, but would rather not be prompted to use it in every fight.
Last edited by CJMPinger; 22/07/21 03:20 PM.