There have been a lot of really fine ERC bows made on here. My favorite bow to date is an ERC I made a couple seasons ago. It's on here back someplace. 66", D style bendy handle, rawhide backing, about half sap and half heart wood, 50 lbs +/-. It really shoots. Killed four deer and assorted other game so far. Thousands of shots with no signs of trouble yet...
Basically, make an ERC bow either long, wide, or backed with something stretchy, such as sinew or rawhide. Don't sweat performance too much. If you get it to the point of being a bow, it's likely to shoot pretty well. It's light in physical weight and doesn't take much set (before it explodes......), so if you can get a reasonably well designed bow from it, it's likely to shoot pretty well. Fun wood to work with and really pretty too.