Steve, some folks recommend a thin CA glue, but from my experience with glass bows you don't really need it if you did a good job with the wood glue. As a matter of fact I've only seen 2 skin jobs that have ever failed, and both were because of the CA (IMHO). They both cracked in a spiderweb pattern under the finish when the owner drew the bow in really cold weather.
As for finish Poly, I'm partial to Helmsman Spar Urathane. The finish holds up great, but takes a long time to cure properly, like 2 to 3 weeks at times. I usually brush on 6 coats, sanding every other coat, and then spray 2 or 3 coats of satin once I'm satisfied with the smoothness.
One other thing. Use SHARP razor blades for trimming the skins. A 10 pack of blades is like $1.29 at Wally World. I usually use all 10 per bow.