Yes carpet needs to be brought back. A more cushioned carpet surface is fast but not a 90s style ice rink or anything, and is safer for players than thinner carpet or hard courts.
There need to be 2 slams on slow surfaces, and 2 slams on fast ones, that reward aggressive baseline play and shotmaking. There is nothing wrong with baseline grinding but it shouldn't be the norm on every surface.
Really there is something wrong when two out of the 4 slams are played on slow hard courts. I would even prefer a few green clay tournaments instead of so many slow hard court ones.