Up until recently I would have said it's too heavy but the flu slowed me down. Sitting in the lazy boy gave me time to think over some of the "facts" that we all know are true.
Osage makes a fine glass backed bow & it's pretty darn heavy. So is glass but straight limb glass backed bows will usually outperform a st limb, wood bow.
I do know for a "fact" that fiberglass is made with fibers. Put a clear piece against a dark background and you can see the fibers and any other faults in the resin.
One of the more memorable bows I've built had a .125" Purpleheart lamination for a core and Birdseye Maple for the back and belly. This was a very light weight bow that really threw an arrow quickly. Purpleheart is heavy.
Try the Ipe for a core wood and get back to us. I'm very interested in the outcome. My only suggestion is to reduce your normal stack a bit. A thin Ipe backed with Bamboo makes a pretty stout bow. I expect it will do the same between glass.