Hmmm...a modulation-only skiff? That's actually quite doable, and it's exactly what we're talking about when we mention "mission-specific" builds. Vide:
ModularGrid Rack
TILES: I went with a Temps Utile with the four-input CV control expander as your master clock + random sequencing weirdness source. Then there's a quantizer, as the T_u can output CV over output 4. The QuadrATT is next, then a tile version of Mutable's Peaks.

3U: Just wait for it...it IS the ultimate in random signal generation and manipulation, a total gamechanger when it came out in the 1970s...and that's the Buchla Source of Uncertainty. It'll hit the market in a few months (I'm betting it'll be post-NAMM) and is 100% worth the wait. Then there's a quad LFO for four free-running sources. Maths follows, then a Tiptop MISO for tampering (a lot!) with modulation signals. This is paired with a Zlob Vnicvrsal VCA, which gives you six "breakout-able" linear VCAs along with the capability of mixing VCA outputs. The 4ms PEG is for generating VERY long-period modulation curves of up to 30 minutes from start of rise to end of fall, all under CV control or with lengths set by "pinging" the module by either a clocked signal OR manual tap-buttons. And last, for more conventional envelopes, there's the Quadrax plus the Qx expander, which gives you EOR and EOF signals that can be routed all over the place, or used with the Quadrax to generate "cascading" modulation curves.

As for mounting this somewhere accessible, I'd suggest grabbing one of these: https://www.sweetwater.com/store/detail/GFWMUS0500--gator-frameworks-gfw-mus-0500-lightweight-sheet-music-stand. Put this stand behind the Matriarch, put the Palette on it at a desirable angle, then you'll have excellent access to it AND the Matriarch while playing. The stand's even fully foldable for gigs.

The overall build is a good bit more than $1k...but it's a great deal more capable than a Palette 62 could possibly house!