If the rack is always going to be hooked to ableton I'd suggest FH-2 instead Pam's. You'd really want to sync clock especally with sealegs. You can sync ableton to pam with https://busycircuits.com/products/alm-pg001 for sure, but you're still going to be bound to the tiny screen on pam while you have an infinite way to control things (ableton). Also less headache tbh, you just hook it up FH-2 with usb and there you go.
For the joystick I'd also suggest you to have a look at planar. It can be also used as a audio/cv mixer, gate trigger and record your expressions. although generally you either wanna use it cv controller or mixer. can't do both at the same time.
As talking about mixers, I'd also suggest to have a look at matrix mixers too. It's a great idea way to route and mix audio. generally they take up quite a space though. 4x mix very is good if you wanna keep things straightforward.
Lastly, you'd need some audio normalisation back into ableton. I wrap up all my audio into HPO if i need a line out. 2hp and just dead simple audio out.
Also mimeophon is a very good alternative to sealegs if you wanna get weird instead of lush. I'm suggesting this as you plan to route your audio from ableton. There are so many (even built in ones) great delays in ableton can sound good as sealegs. I'd say if you're routing to eurorack, I'd get someting weird like mims.
Apart from all these; to contratict myself, if you have a spesific idea what you need, you can always go for pedal fx's as well (which are going to cost wayyyyyy less than eurorack). Pretty much you can get a single pedal for each module you've put there. I'm talking about expensive ones like chase or hologram ones.
Good luck with the hunt :) Let us all update what you've decided.