Just a bit of a status update.
Most of the groundwork is in, all of the attributes are working, four of the Proficiencies are working (Just haven't made the other three yet), and three of the tiered statuses are fully working and the rest should be relatively easy to implement.
There's been a lot of other work done but most of it is just tedious stuff that needed done (Over 6 pages of addresses from a localization file I've modified for example), but by and large things are going well.
When all of the groundwork in completely I can then move on to adding skills, which I expect to be extremely tedious and take a while, but once that is done the mod could be considered "playable". I'll still need to go through all the encounters for adjustments and make them use the new systems and play through with the mod multiple times to make appropriate adjustments to everything.

Regarding compatibility: Mods that modify charScript files will very likely be incompatible. This is basically unavoidable with the scope of the mod. A lot of mods that add classes will probably still sorta work. Statuses used in the mod that have been swapped to the tiered system will work with the tiered system.
But given the changes to armor and damage they'll have oddities such as anything that does Physical damage will instead be doing Light damage with my mod and anything that requires, for example, Huntsman will find it instead requiring Divine.

Compatibility patches for these kinds of oddities should be exceptionally easy to patch (And I may make a script to generate said patch), but balance will of course be up in the air.