So I get this straight, the middle ages English hack would be standalone but then all your current bugfix options could be applied on top of it? Sounds like the right approach if it's all compatible.Yep, completely standalone. It'll be one or two main patches (hopefully) with various addons containing the rest of the options available like Liberties and a patch that shifts the Masamune to Grandleon (along with Masa and Mune to Gran and Leon). They won't be in the beta though.
Also, I'm curious what your vision is for changing Frog. I was under the impression that everyone else would end up sounding like Frog and that he would simply fit right in.
I'll be on it with feedback as soon as you launch your first beta
Of Frog himself, there was an idea that Digitsie brought up earlier of a localization trick for making Frog still stand out for various character reasons: The Middle Ages would play similar to Frog's normal speech, but Frog would end up being even more archaic. I'm still coming up with the nitty-gritty for that, but it was theorized that a more archaic Frog would come off similar to Vagrant Story or Slattery's Final Fantasy Tactics at times (but not always). This I'm probably going to end up either making into a second patch or an addon; the reason being that some I realize just want everyone talking the same like Ayla and the Prehistoric Era, and he may end up becoming less readable to some (a common worry about these sorts of things, another reason why this whole thing is standalone).