Hi'ya
I'm going to speak from my experience. Since I mostly used Ilusion software in creating scenes rather than play the game, I have seen new mods upcoming that make me think in redo some old scenes; Some remarcable mods are from an Modder named Ekan, that uses innovative tools to make more realistic the movement like Hooh's stuff once in a time; there are new clothes from GDC, and sjjpl, new maps from Mas75, conquestus, etc. just to mention a few ones. The last time I ran the update manager it shown a bunch of new mods, and updated a lot of them too.
Perhaps you are asking if it a major improvement in gameplay, the last repack is Ver. 14. I still using BR13 since my old computer can't manage the new bePinEx that R14 uses to work, i think it iproves some graphic stuffs like hanmen shadders or so, but i can't tell for sure