I have zero experience with ERC (eastern red cedar), but I agree that bamboo is probably not the best choice. Although I've seen a few bamboo backed ERC/juniper bows (google 'booniper'), it's tricky to get it right. Maple, ash, white oak or elm would be milder backings be a better match to the compression strength of ERC. Save the bamboo for a more compression strong wood. ERC is not really compression strong, but it has a very high elasticity.
On the other hand, you are right that a highly crowned back(ing) will alleviate some of the compression forces from the belly. A highly crowned (or trapped) bamboo backing will have a higher chance of success than a flat bamboo backing.
It sounds like you need a powerlam in the handle. Run a (Google) search for the word powerlam. It's placed between two layers (for instance the belly and the core, or the backing and the core which I personally prefer) and not on top of the belly. The powerlam is about 1/8" thick and 18" long and beefs up the handle area just enough to shift the main bend away from the handle. However, it must not be too thick that it will create a really stiff handle. 1/8" thickness or maybe 3/16" is plenty. If you wish to add a riser (in the form of a block of wood on the belly side of the bow), you should still place a powerlam as well, as this stiffens the handle area sufficient to prevent a popped off riser block. A powerlam is easy to make, if you have a beltsander, and really makes for an easier tillering and safer handle.
You can scrape off the rind from the bamboo, or leave it on - it's your call. But whatever you do, leave those nodes raised! Run a search for 'rind' to find some topics from the past, discussing the subject.
