Once dialed the paddle up game what is the lower volume (related to rider weight in kg) possible to still manage the pop up without too much sacrifice?

Is there any advantage regarding stability when the board is semi sinked? Of course this depends a lot on the conditions and would be manageable on strong winds and better bumps but I wonder mostly on my local 14-18kn conditions.

I see most production sup boards starting from 80-90L. I am stepping down from a 83L (+20L) to a 73L (+10L) a few inches longer and 1 inch narrower hoping I will gain some paddling speed so I may use a smaller and faster foil (lift 120) but wonder if I am sacrificing too much flotation for that.

Pretty happy on a Kalama 5'9" at 95 litres. I am 94kg. That's in wind swell type conditions. (City/bay)
I am sure younger or more athletic people could go below weight/volume.