Good points on the Maths vs. 3xMIA. Being a newb - and not knowing what you don't know - isn't helpful. I think I'll plan for the 3xMIA in future expansion. I really should go through that patch guide for Maths to know exactly what it entails.
With regard to uO_C - I'm on the fence. I'm leaning on holding off and leaving space to populate with a few 2 HP modules and FX AID... not sure if going with the XL version is in the cards.
The issue at the moment is I'm not sure what I'm trying to solve. Or I should say I haven't learned enough of my current gear to know what is truly missing. Yeah... I'd say generally FX and sequencing. I'm thinking it's best to take my time with the last 11HP and not make any rash decisions. I guess the question is... what will have the most impact on what I can do within current confines?