I've often thought about it; seems like I always have A65s with dual-carb heads even though I'd be just as happy with a single carb.
I've got a single-carb head sitting on the shelf, and it would be easy to rejet one of my carb bodies for it, and just use it on the Firebird. No more having to sync carbs, and do everything twice, etc.
But I've never gone to the trouble. To be honest, a properly sorted set of Amals with sleeves will last a long time (been 30,000+ miles so far and still starting and idling easy). And I guess I do sort of like that little bit of top-end "kick" that you get on a dual-carb bike; and two carbs aren't really that much trouble.
But if you need a new head anyhow, and have to source one, NOW would certainly be the time to convert. Just make sure you get the right size carb and jet it right.
It should be fun "getting back into" the old bikes!
"What's the plan?"
"Plan? There ain't no plan!"