is it possible to combine grimarillion with good-looking mod?

One of them is open sourced and one isn’t, im new to both modding and grim dawn but i have a fairly good idea how to go about doing it if i had the tools to unpack, and repack

AFAIK these mods shouldn’t have a compatability issue, right?

http://www.grimdawn.com/forums/showthread.php?t=39701
http://www.grimdawn.com/forums/showthread.php?t=46352

You do have the tooks to unpack and repack, they come with GD.

No idea if there is overlap, but that generally is easy to find out and resolve (use something like WinMerge to identify the differences gs vanilla for the overlap and then merge them).

There would be no compatibility issue.