Thus far, it's OK...basic monosynth sort of setup with a LPG down at the end. A couple of things come to mind, tho; first, consider a second VCO. The Morgasmatron is set up for dual inputs and while it also has dual outputs, it also has its MIX out, so you can feed two VCOs in with some waveform differences and have a little more timbral variation. You can also double them up via sync and get weird harmonic sweeps, put them in different octaves for octave doubling, or just double them in the same octave with a little offtuning for a really big sound...this last one works well on basses.
The other thing is that you might consider a second envelope. The Function will be great for controlling one of the LPGs, but you have two of them, which means you could just as easily have different envelopes for each channel the Optomix is mixing down. Also, another major use for second envelope generators, seen all over the place on loads of monosynths thru history, is to have a separate control envelope for the VCF. But seeing as how the Morgasmatron is two filters in a weird cross-relationship, the ultimate number of EGs you might want is actually four. And that's easily fixed by yanking the Function and switching to something like an Intellijel Quadra. Very easy change there.
With the Yarns in place, you're set for expansion as well. Once you get the basics sorted, that's one to keep for building up a larger rig. But it comes to mind that if you're thinking about that acid sound, the sequencer also matters quite a bit, since the glide function of the TB-303 was part of the weird pitch+filter sweep sound. So, why not kill two birds with one stone here; have a look at the Arturia Minibrute 2s and then conjoin that with a 6U Rackbrute, which comes with power, and is very cost-effective plus offers lots of expansion space. Plus, the patchable Minibrute 2s architecture means you can also insert its individual circuits into the modular setup via its patchbay...and nowhere in all of this are you really getting in so deep in modular synthesis that you'll find yourself out of your depth.