We need to make a list of mods that can be added with the JGSME program that will work with HSFX...

and make this a sticky if possible.

should be easy....
stay away from addon aircraft

all other mods should be compatible, as long as one stays with the basic mods file structure and addon process in the various ini files, known from the AAA mods;

So as long as it does not involve changing .ini and property files, it's good to go?

ehm, yes and no;
you should be able to add all stuff except aircraft, because these needs a dedicated buttons file to work properly;
so far noone has posted if a new buttons file from the AAA team will open up new planes to HSFX, but I do not think so, as HSFX contains not only AAA addon planes, but also some from other teams;

so as of now, stay away from new aircraft;
maps and other stuff should be ok though, even if they require some work in the various ini files, Canons great map is a good example here

Canon's map is already included.