Congratulations on your DIY project, posting the commercial version was not at all intended to throw shade on it. I've reverse engineered plenty of commercial products, both for fun and for profit and know the challenges.
HoHoHoH20 has been ok but not perfect. I had to 3D print a secure mount for the probe to fit my tree stand. They don't really include any kind of mount, the probe kind of hangs on hope and prayers.
The pump doesn't develop enough head pressure to lift water more than 8" or so, which it needs to in order to get over the rim of my tree stand. So when the reservoir is getting low, but not empty enough to trigger the low water level alarm, the pump just runs continuously but water does not flow. Found this out because my cat was curious about the pump noise. The easy solution was to put it on an 8" pedestal.
Anecdotally - we have found that Nordsman Fir trees consume a lot less water, drop a lot fewer needles, and have strong branches that can withstand heavy ornaments and cats. Worth seeking out.