I have done quilts with elements *sticking out* from the main lines of the quilt a few times- I sandwich and quilt them as normal- then trim the batting/backing around the features that stick out (along with trimming the whole quilt) then I use a facing instead of a regular binding- facings are quite easy- if you do a search (*finishing your quilt/facings*) you will find lot s of videos, tutorials on the technique- it is a great way to go when your quilt is not a traditional square/rectangle.