All these great ideas... How do I start?

[Quickleaf]

In order to get to all this I need to establish the start of the adventure. My real question comes down to this more or less: How do I avoid essentially having an old man approach them in a tavern and give them their adventure. *Or* how do I make that experience interesting?

So your group begins in a village hiding out from some enemy in a position of power, then one day the enemy arrives in the village, right?

I'd set it up as a game of cat and mouse. No "old man" needed. The PCs need to avoid detection (or at least getting cornered) by a superior force, yet at the same time that enemy has information the PCs need. Begin the first adventure with the enemy just arriving in the village and turning it upside down. You could run this as a skill challenge to remain hidden, with several decision points worked in (eg. their enemy threatens to torture/execute PCs' loved ones if they don't show themselves). You could weave a couple skirmishes into this if things go poorly, fights the PCs need to resolve quickly before reinforcements arrive.

That would make for a dynamic start which gives a strong direction (just make it clear what they need from the enemy & that the force is way superior) while allowing for lots of PC ingenuity, and sets up the villain and possibly ally NPCs for future adventures.