Front Crawl breathing prob

On my right side, which is how I learnt as a kid, I tend to find that I don't balance in the water as well as when I breathe on the left (the side I forced to learn bilaterally in recent months). Feels like my lead arm (left) goes down (I think that's a reflex in trying to push my head up), and I've worked on holding the stretch. That didn't fix it. Still feels like I begind to sag in the water. I have now been tinkering with pulling back further on with the right arm (because I started to cross compare) to getting a better roll and glide; this seems to be working a bit. Does that make sense? Is cutting the pull short (in slower paced swims) likely to cause a sagging feeling? Undoubtedly I have a bad habit well ingrained...and without a coach to look at my stroke it's a bit of "cat and mouse" for me to analyse. I have books with drills etc but I want to try and ID the issue if I can. Sprints are not such an issue...but there are less breaths and faster turnovers. Any thoughts? Thanks Rich