Our posts crossed and I didn't see your reply, so here is an addendum. For evolving textures in Eurorack, I look to slow modulation sources that can provide CV to FM and wavefolders of VCOs. To complement my Elektron boxes and other out-of-rack gear, I look to analog VCOs with, well, lots of modulation options. I'm not particularly impressed by wavetables, in or out of rack, but this is a personal opinion. My VCOs are Frap Tools Brenso and (just arrived) Joranalogue Generate 3.
I have a DB-01 and love it, so I understand your thinking, but: the DB-01 is a tweak on the Erica Synths Bassline module, and you may have noticed that the output is really hot? If you turn it up to max, it is at Eurorack level. So you can turn the DB-01 envelopes full open, and then feed it pitch, gate, and filter cutoff CV, and take the output straight back into your rack for further processing. Yes, you can't use the DB-01 filter for anything else, but you don't want two of those sounds around, really. Of course, you can just sync clock, use that great DB-01 sequencer, and mix in the sound separately.
Delta-V is my suggestion for replacing Maths. It doesn't have the logic or skew limiter, but you can get those from Disting (one at a time) and see if you need specialized modules for those purposes. I chose Frap Tools Falistri over Maths, but that is more of a boutique choice, and I wouldn't necessarily recommend it to everyone. Each of the two Falistri envelopes does quite well as a VCO that can track V/oct while holding pitch as shape changes (for timbre), unlike Maths. Quadrax can do this also, but with less timbre variation, and more nuisance in dialing in pitch, and it doesn't sound as good.
MI Stages is another matter, and what I am watching in this space is the announced but not yet released Joranalogue Step 8. At this point, slow acquisition may be forced on you, but that is not necessarily a bad thing. Just try to get an initial set of modules (50-80 hp at most) that are usable and will not frustrate you.