if other (gnminer and many other miner) can do core and mem from command line i'm sure you can do it too
Yes. It can be done, but most of the miners are using hivos, raveos, mpos and in these os'es you can set the clocks. Msi afterburner is good, you can set clocks, templimit, fans and let the program remember the settings on the next boot.
There are other more important issues to fix. Like faster AMD and LHR unlock..