I don't leave but a couple of stitches between pieces when I chain stitch. I never have thread breakage. I have found some thread spools have thin pieces of thread on them or other flaws, get past those and will sew much better. Never use to have that problem with any thread, finding those areas more and more. Never affects thread in the bobbin.
When changing bobbins I always try to jiggle the bobbin to make sure it is in there correctly. My machines have side mount bobbins and a small space.