There is an update blocker for future updates, but the updates with games are going to be lower than 4.55 because you can't play any games with a firmware higher than 4.55, I have heard mentions of a fan control app in progress, but not seen anything concrete so far, other than that, there are some other features, what is it, that you bought the PS4 to do?
Haha playing games!? i'm also a PS2 fanatic even though i got a PS2 and a PS3. but i still wanna play these on the PS4 and maybe try those enhanced versions as well.
btw i'm surprised, the PS4 is like 4 years old and yet there's no JB a full one that is. i know it's a start. hopefully they get the job done before the relase of the PS5 in 2020.