I think Maths is a better starter than, say, Ears in this case, actually. For starters, it actually does everything Ears does except the contact mic stuff, which is pretty easy to set up at home. You can start by using it for simple duties (envelopes, complex modulated LFOs, logic, and yes, envelope following like what Ears will do) and then explore more concepts though Youtube and the manual. It can even make an interesting filter or traditional oscillator to experiment with. From there, it'll be pretty easy to figure out which of the functions you use separately enough to warrant its own module. Having both at some point will be helpful, but for now having a Maths alongside these modules will allow you to experiment with multiple robust and musical case arrangements/patches in far more ways.
Do you like the Doepfer A-143-3 specifically? I love Doepfer modules too, and that one does seem nice and roomy, but it doesn't seem to offer a lot of flexibility. 12 LFOs, but only four speeds/rhythms. No voltage control, even. It's also not as cheap as I expected. Free-running LFOs like that are awesome and help make modulars feel distinct and free, but there are a lot of options there that might get you more for that amount of space and not much more money. Batumi? Ochd + expander? Lots of options.
Just my two cents on those issues. You seem to be on the right track. Knowing why you're doing what you're doing is more important than doing any one specific thing.