Great advice from Jim here, and note he also included NaN, the expander for Zadar which I think is a must-have, especially for ambient types of music that will greatly benefit from the additional CV input per channel and the ability to trigger the shapes manually.
I also think that for a build where space is limited, the FX Aid is an instant win, absolutely gorgeous sounding algos and again, I think Jim's choice of the XL version is a good one for your type of music, the additional CV input and the CV over sample rate is pretty useful.
Something else to consider in such a small build: do you really need that buffered mult ? If you remove it, you'd have space for an Erica Pico module, for example, and you could use inline mults instead...
And also another vote for Jim's advice on a bigger rack, if you can afford it of course, if you don't mind the small-sized modules a 7U 104HP would get you far ;)
Actually I could've just written "Jim was right" and called it a day