My perspective in addition to the good advice given above:
Aesthetics are cool. I think they are important. I always make an effort to organise my rack using aesthetics as one of the guiding principles - it does make a difference to me. Of course this does not negate functionality, ergonomics etc. and you should always consider these too.
I would highly recommend an Envelope follower and gate/trigger generator:
https://www.modulargrid.net/e/mutable-instruments-ears
or if you want something really nice:
https://www.modulargrid.net/e/xaoc-devices-sewastopol-ii
These will allow you to take the sound AND the signal information from your bass guitar to influence your modular synth.
With this as your starting point, think about the kinds of things you would like to do with that envelope follower and gate/trigger/
e.g. each not played on your bass guitar could trigger a sequence played on the modular or a sample playback or provide the clock for your sequencer, an envelope for your filter cutoff, the possibilities are endless.
The point being is that you need lots of ways to process that incoming envelope and trigger - so as BORING as it is I would highly recommend a multiple and a clock divider/multiplier - so ONE trigger generated from playing your note on your bass guitar can trigger a whole sequence of events or events that only play once every four notes etc. etc.
Finally once you have melted your mind trying to figure out the millions of things you could do with clocks, triggers and envelopes, look at additional sound sources and FX modules.
I would also highly recommend looking into wave folders, tone shapers and compressors - ROAR!
Have fun, I too look forward to seeing what you do here :)