I think you'll just need to nudge him (or whatever else you do to get him to quieten down) if he gets too noisy. It might help if the seat back is raised a bit, although it may not be as comfortable for him.

I find that snoring is much easier to block out with noise cancelling headsets etc than screaming or laughing.

Having said that I certainly go as far as to wake my husband if his snoring is affecting other passengers. I see it as my wifely duty to ensure that he doesn't annoy other passengers