Tbf the existing toilets are pretty disgusting. I am glad they are having an upgrade. At the moment they are accessible from the street so anyone can walk in - gender neutral loos accessed via the cafe will probably be safer.
I would prefer single sex but can see how gender neutral will help with baby changing.
I've noticed a few places in Brighton (Ask Pizza I'm looking at you) only have baby changing facilities in the female loos
so nowhere for dads to change the kids.