I'm wondering if anyone can let me know if there might be anything glaring I'm missing here. Possibly more utilities? I know I should get a buff mult and mixer, but is there anything else that would be recommended? I'm looking to make ambient, sorta shoe gazy, experimental music. Any module suggestions I'd be grateful to receive!!
ModularGrid Rack

First up, you've got some discontinued modules in this. That Pitt output module is out of production, and the Tiptop EG has transitioned to another revision. Secondly, you won't need ANY mults in this, as the build is simply too small to give up functional space for something that should be dealt with in this case with inline mults. As for the need for a buffered mult...this only comes up when you're trying to send a scaled CV to so many VCOs that you get voltage sag, which throws the scaling/tuning out of whack. Not enough VCOs here to require that.

The way I see it, you've got two choices here...

First up, start in a bigger case. And I mean REALLY bigger. Then scale this back to a more practical result...but step on up to 2 x 104 or such.

Second option: shrink the modules. Do you actually NEED those large modules, or can you reduce the panel space by substituting other modules, smaller "clone" versions, etc?

In truth, BOTH of these options should be kept in mind while reworking this. Also, if you have a specific musical idea in mind here, look around MG for builds by others doing this...there's quite a few. The general idea you're on is right, but there's a lot of miscues here...such as the O/A/x2. It's $100 for a pair of offset gen/attenuverters. But for $9 more and 2 more hp, you can get Intellijel's Triplatt...which gives you those functions, adds one more attenuverter, then sums all of the inputs via a "breakable" summing bus, plus it also has a couple of "hidden" functions. Since the idea is to always push functionality, it makes far more sense to find those extra 2 hp to put one of THOSE in. But there's several points of that sort where it appears that a bit too much YouTube has crept into the build...and tbh, there's only a handful of YT presenters that I consider to be conversant enough about modular that I would listen to their (unpaid-for!) advice. It's far better to work these issues out here on MG among the "working modular stiffs" instead of watching a presenter with fairly "opaque motives" that might be telling you something based on getting some compensation such as a freebie module, and NOT on actual use and experience.