Nah, keep the Plaits...you've got it plus the Shapeshifter in this cab, and that gives you loads of digital sourcing. QCD + expander, definitely...loads of timing control potential with that. As for the Doepfer A-106-1, here's a sick and twisted idea: use its resonance insert, put the Chronoblob in it. Then take the Chronoblob's feedback insert and drop something in THAT...filter, some other processor, etc. That's what's fun about that thing, aside of the MS-20-type filter architecture. You could even set up feedback loops going back and forth from the Doepfer to the Chronoblob, and back again. Plenty of ambient drone/texture possibilities there.
Delay...here's an idea, albeit a bit spendy: Verbos's Multi-delay. Note the presence of envelope followers on each delay tap, which opens up a lot of strange amplitude-control possibilities elsewhere in the rig. And tap 8 has the reverb/octave shift on it, which has "ambient" written all over it. Same size as the Magneto, too.
Smart move with the Stages, btw...two is very much better than one there!