Our first boat board was the 4.9. We still use if for newbies, although I removed 2 of the 3 fins so we can get a good attempt at a surface 3.
I don't know about progress quicker, but the 4.9 can do spins easier but also likes a bigger wave especially for those 200lb folks. If you don't have a pretty big wave, the 200lb peeps will have a hard time learning and staying in the pocket with the 4.9. So I'd say the 5.6 is easier to freeride and practice control---which is what these entry boards are about. Have fun.