If this were me...
I would look into more LFOs and/or function generators for sure, but I would also look into modules that kinda take one or two inputs and turn them into lots of related outputs. In addition to the Multimod mentioned above, examples include:
- Mystic Circuits ANA 2
- WORNG Vector Space
- Ritual Circuits Anima or other shift registers
- Black Noise Cosmos
- Nonlinearcircuits Let's Splosh
The latter two can be found for free on VCV Rack if you want to play with them. A related but slightly different approach is a joystick module, which is not only just fun in general, but is usually another really interesting way to engage with the modulation you have in a broader, stranger sense.
A quantizer might be good here as well. That way, you can kinda just throw whatever in there and see what melodies come out, and it also gives you more options in terms of creating unique sequences by having your pitch and gate information come from separate sources.
This is a little crazy. but you could always try a module like the ES-8, ES-9, or Boredbrain Optx v2 (if you already have an interface with lots of channels and ADAT) and experiment with a hybrid setup as well (hardware and software modules). Even if it isn't permanent, it may provide some new ideas and let you use some modules you weren't considering before. An interface with DC-coupled outputs will let you send modulation from the computer as well as audio, allowing for full integration of the two sides of your setup.
It seems like you have plenty to work with, but these are my suggestions for how to spice things up.