Just finishing off my last couple of jobs before disappearing and thought I'd relate today's experience of one reason why I'd urge you not to go down the "whole-house" GFCI approach.
This was a big house converted from old barns -- Bathroom the size of my living room and a living room the size of my whole house; the guy paid £300,000 cash for it (about $450,000). Waaaaay out of my league! But that's irrelevant....
O.K., I was working in the yet-to-be-finished barn/garage area, having gotten several flood lights fitted high up in the 1830s beams. It was dark by the time I got to the recepts. so I turned the floods on to continue working, and shut off the 32A C/B for the recept. ring.
No problem you might think. Well, guess what happens when you take a pair of cutters to a cable and they momentarily bridge neutral and ground. Yep, <click>....<darkness>. I was expecting that.
Having descended the ladder in gloom to reset the breaker, I went back up to strip the cable ends and accidentally brushed the stripped neutral onto the grounded fixture box. D***! Back down
to the panel again. I managed to short N-to-G once more in installing that fixture. (At least the RCD/GFI is working!)
See why I don't like this arrangement?