Hi Nicholas
things I've noticed
you can probably drop the quantizer - metropolix already has one built in - so unless you have a specific use case I'd leave it out (at least for now)
the expander for batumi is useful
you probably don't need a pair of buffered mults - I would opt for a links instead as it will give you a couple of simple mixers too - the top one of which can be used as a buffered mult too (and as a precision adder) - often all you want for a mixer is to add a couple of things together gates for example and these are perfect for that too
i'd go slowly with mixers - get the quad vca to start with and then work out what you actually need as you need it - I started with a veils and a rebel technology mix02 - which was a fantastic combination especially as I also got a headphone out - so it really depends on what else you are getting in your first batch of modules - if it were me these would be plaits, stages, metropolix, the quad vca and the black hole dsp (but I'd substitute a fx aid xl, personally) with kinks and the triplatt hot on their heels - it's possible that the next module you will want will be a mixer of some description
other than that I don't think I would plan any further - you will work out what you want/need as you patch
utilising utilities: take a modulation source patch it into a utility - to multiply, modify or mix it with other modulation sources in order to make more interesting modulation sources - slow lfo mixed with fast lfo, a slow lfo opening and closing a vca that allows a faster lfo through, mix this with an envelope that is opening a vca for a vco to get a tremolo effect at the end of each note, attenuate an lfo or envelope so that it's effects are less, invert it so it does the opposite - ie closing a vca instead of opening it etc etc
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities