building with rock naturally fixes a lot of this problem. Rock is thick enough that the terrain clipping is contained inside the wall, if done carefully. A second wall thickness can be added if necessary.
you can also cover holes with tiles; at the top of a raised ring or square, I often have a little gap between the building and the terrain wall, and I just put down stone floor tiles over it.

if your raised terrain is of any height at all, it will ALWAYS be some sort of near pyramid slope that while fairly upright and straight, will never be perfectly so. That means if you build say a wood wall that does not clip into it at the bottom, it will have a gap at the top. If you clip at the bottom, you can close the gap, again easier with stone but you can make a 3 or 4 wall thick wood build too. At the end of the day, make it look right is going to take some unnecessary filler or cover up but it can be done if you want to do so.