I've been spending a ton of time working on acid racks so I spent a few minutes on this and came away with the below:

ModularGrid Rack

Some notes:
1) I extended to 104HP because that extra 20HP can go a long way for us here as you'll see.
2) The biggest and probably most important addition from my POV is the Make Noise Pressure Points. This lets you easily create 4 part song structures, with let's say two of the inputs going into the meloDICER and a third controlling the Bassline filter cutoff... all of a sudden you can easily change chords and dynamics across multiple parameters with one press. Not to mention it's playable, you can use pressure to drive CV changes through the top outputs, meaning you have structured control of 3 parameters and expressive control of a fourth, lots of fun.
3) I added a WMD Time Warp for gateable slew and as another envelope generator.
4) I added a Bin Seq and a Tree to get weird gate patterns going. This isn't something I've tried personally so you could take another route and add a temps_utile or an Intellijel Steppy and get good and perhaps more grokable results that way too.
5) Pip Slope as a backup envelope generator and also as an LFO.
6) FX Aid because it's got huge range and is superior to the Delay and Verb at their own game from what I can tell.
7) A Disting MK4 to fill in any number of possibilities, wavefolder, recorder, tuner, more effects, etc.
8) I left 4HP open for you to fill in with a distortion module of your choice, I couldn't pick one (though I love the Manhattan Analog DTA) but ultimately the Erica Synths one felt like it took up too much space so I cut it.

Some alternate possibilities worth considering:
1) With Metropolix coming out Metropolises will be going on sale used at a discount I bet, probably worth comparing to the melodicer, in which case you could cut the Time Warp.
2) I recently got an M303 and love it, compare it sound wise to the Bassline and throw the X0X Heart in there too to see all the voice options out there.

Hope this is helpful, and let us know what you end up with!