I've gone from a having a mild distaste for the current state of T4 to a more generalized disgust as the years have gone on. It's just too long, the moving walkways are always broken, the escalators are backwards (favoring left-hand traffic), the busses are slow and unreliable, and the headhouse and roadways are unholy messes. The only SC is cramped and crowded, and a far walk from the regional gates and the base of the concourse where the bus station is. Getting lucky when a flight of mine goes into or out of T2 gets me unreasonably excited.
I pity the fool who needs to connect from a regional jet to a concourse A gate. The shopping mall connecting A and B doesn't have any moving walkways and is a lot longer than some people realize. I know a people mover isn't in the works, and I can't see a tunnel under the tarmac being built at NYC construction prices to connect the far ends of A and B. The only hope is for more slow, unreliable bus service, but this is not a "best-in-class" airport experience by any means.