I'm just a wannabe game designer, but what comes to mind for me would be to apply an entire board Conway update every X (4?) turns.

I think it would be a bit easier to mentally manage than having every piece on its own count

Might give an edge to whoever goes second, because they will have more control on creating overpopulation conditions right before an update, which would offset first move advantage

That sounds like it could be fun! The multiple turn delay I used for this may help solve some of the problems of the pieces dying immediately at the start, and for the end game where too many deaths would cause the game to drag on. Births could probably have a smaller delay than deaths. I could see this make for interesting plays by opening holes in your opponent. There's also the choice of whether births/deaths take into account all neighbours or just your own pieces.