Ne-LII INTj, 5w4, not sure what else. But hey!
As you might guess, I'm more or less new to this. Looked through MBTI for a while before discovering Socionics. It was actually over on Amino, if I remember correctly? But anyway, I find that it seems preferable since I reckon being relatively more informative usually makes up for the extra dose of complexity, as I suppose my own typology would have me inclined to think. Some specific topics that I'm not yet fully clued up on are the 2 additional enneagram types (since I find profiles where they often have 3 in total), as well as instinctual stacking (although it might be something like sp/sx or sx/sp, I guess?).
Well, hopefully that says just about enough for an introduction!
Welcome, 2 additional enneagram type comes with tritype theory. Different people think different theories or different models of those different theories held true, you can check and find out what clicks for yourself.