I have 2x quadratts and a Noise tools, and I can vouch that it makes a pretty sweet 1U row!! :-)

Ok, now just for thought...

I very recently managed to make myself a Poti in only 2HP of 1U space (and I see you have a 2HP gap). This didn't even require soldering to assemble, mainly you have to very carefully drill 3 holes in a blank panel using a template.
https://www.muffwiggler.com/forum/viewtopic.php?t=192446&postdays=0&postorder=asc&start=25

As for the dual ADSR, if you wanted to free up some more space.. You could go for a Doepfer A140-2 8HP 2XADSR. I've personally been eyeing the upcoming Doepfer A-142-2 which is 2x AR envelopes+VCAs with ducking, in only 8HP (bonus, you get more VCAs!).
https://www.modulargrid.net/e/doepfer-a-142-2

Well, that'd make 9HP more to play with. Rather than going super-high-density, you could use the HP to replace some of those really tiny 2HP modules with bigger and better of the same.