Great system, and sorry I'm arriving 2 weeks late!
I also do DIY, dipole, AMT tweeter driven by SET, although have 4 sealed DIY Rythmik subs. And use DSP for digital xo and room correction. I use Acourate software for this, and believe Audiolense is also great. A great write-up by Mitch Barnett can be found at Computeraudiophile from years ago - there is a basic walk-through and an active xo walk-through, where he explains the setup and process, and results. He late wrote an ebook, and did an article on Audiolense I think.
My setup is an "audiophile" computer running Roon, convolving filters made with Acourate that account for linear phase xo and digital room correction (and time-alignment, etc), that outputs to a 8 channel DAC (Lynx Hilo) thru USB, that drives 8 amps directly connected to the drivers. Hilo has DAC and ADC capability, which is important to take the measurements to create the filters to be convolved. This is sort of the DIY approach to what boxes like DEQX do. One ADC/DAC I've had my eye on is Merging Hapi, but haven't gone there yet.
As I started venturing into active xo, I first used the Rythmik xo to relief my tube amp from reproducing sub frequencies. This was good, but going active with Hilo/Acourate far surpassed this solution. To me there is no going back. Given your DIY skills and willingness to dedicate time to get it done, I suspect you'll be on a similar path.
Please keep us posted on your journey!