Sounds like you've got a lot of fun and nifty ideas, but a lot of them are handwavy "This'll make things all better when X happens or when I decide to do Y." Unfortunately, X doesn't happen nearly often enough. Instead Z, Q, and π happen, and all the careful planning and hard work you spent on X morph into another learning experience. And you may never even get the chance to try Y.

Start figuring out the miminum that this thing needs to do, other than the irritatingly vague "it can run on a laptop" (Bosses, don't you just love them)

Worry about the multiple-interface SOAP frontend later. First just write the app they asked for, if that's possible :)