Shaped Sheet Initiative Help

I am a Pro user running a game here on roll20 and we are using the shaped sheet. I am having trouble with a few things related to initiative. For this campaign we use the following formula for initiative... d20 + dex + wis + proficiency bonus to determine initiative. How can I add that formula so that it works with the shaped sheet? Additionally how do I can other modifiers that may come into play like the Rakish Audacity ability that Swashbucklers get or the Tactical Wit ability that War Mages get?

I would do that with a Modifier.  You'd need to add it for every character (and I'm not sure about Monsters?), but it's pretty easy: I don't know what those other abilities are, but I'd be willing to bet you can get them in there with Modifiers.  I use them for all sorts of things.  Feats, Cover, Shield spell, Shield Guardian bonus, Magic Items, etc.