There doesn’t seem to be a lot of development in this field. The large gun is probably the most reliable tactical weapon in an arsenal. It can sustain a high fire rate. Its inexpensive to develop compared to rocketry and manned aircraft. It can throw out a lot of material over the target zone at a relatively low cost. Its pretty much an all-weather weapon. It can be built very quickly.

Here’s a few of the weapons used for awhile post-WW2:

M1 (120 mm L/60) 25-mile slant range at up to 57K ft altitude @12rpm
M2 (90mm L/53) 12-mile slant range at up to 34K ft altitude @25rpm

QF 5.25-inch (133mm L/50) 15.33-mile slant range at up to 55K ft altitude @10rpm
QF 4.5-inch (113mm L/45) 13-mile slant range at up to 44K ft altitude @8rpm
QF 3.7-inch (94mm L/50) 12-mile slant range at up to 40K ft altitude @10rpm (20 rpm for the fixed site)

KS-30 (130mm) 19-mile slant range @60K ft altitude @6-8rpm
KS-19 (100mm) 13-mile slant range @50K ft altitude @12-15rpm
M1939 (85mm L/) 7-mile slant range @35K ft altitude @10-12rpm