To answer your central question.. with Art Quilts which this will be... it is your creation .. you can put whatever techniques in it you desire and use whatever gets your design done.
But before deciding on techniques I think you need to design your quilt top and decide what size the emblem is to be. Larger may very well be easier... however.. pearls of that size might be a dealbreaker.. so you go to a fabric that conveys the sheen and idea of the jewel. Once you get the emblem done "to size" it will be much easier to make design and content decisions. I think this will be lovely.