As for tillering, I was told it would be better to do this as a 2 part glue up. Back and core first, tiller and work to about 15# under the weight you want then glue on the belly.
Of course, I didn't get this advise until we had already taken the completed bow from the hotbox
Before the glue up I tried to make sure all my tapers were as equal as I could make them so the limbs would bend evenly. I staggered the nodes between the back and belly so as not to have any stiff spots.
After the glue-up, following more advise, I trapped the back of the bow first so I wouldn't overpower the core and belly, working the limbs a lot after removing equal amounts from both sides of the limb.