For a show you would have to tie off and hide in fabric. I always ensure these ends are about 6" in length long enough to tie and pull through until the knot goes pop into the fabric. I would say you are not leaving enough tail. I dislike the cheats needle I use a needle with a large eye. Length of thread depends how long this needle is.
If quilt is for friends etc I micro stitch and cut off. As long as the threads are securely fastened no problem.