I have a BIA. I've always had issues getting it to play well with others... especially when trying to tune it.
Everyone starting out buys a Wasp Filter. Everyone then sells it.
For its feature set, the A-118 is pretty big. If you can find a smaller noise-generator like a 2HP unit, you can claim back even more HP.
I'd want the following:
A dedicated LFO that can sync and reset.
An analog VCO that can get down to LFO rate: like the Dixie II+
Utilities like attenuverters as well as another small mixer that can handle CV OR audio. You can do this with the Maths module. But you might consider a dedicated module if you find yourself choosing between using the Maths for this versus other functions.
A Disting EX as a jack-of-all-trades to experiment with or try different types of modulation or effects.
Two envelope generators. Maths can be used as two AD envelopes. But relying on Maths as an everything-module will limit your creativity.
I'm also a big fan of Ornaments and Crime. It can do a lot and isn't that bad to navigate for a menu driven module.