Are you in the United States?
I'm just curious how your homeowner's insurance feels about this? That is, will they still pay out for a claim should something happen, and they determine your modifications were at fault?
Because if the adjuster or whomever does find you have such modifications - they -will- blame those.
And probably deny your claim and coverage (and probably cancel your policy).
At least that would likely be your experience if you live in the United States.
I've often thought that having such a system would be fun, but the potential downside should anything go wrong has put a damper on it (even if whatever happened was not related to your modifications - they will blame it on them, just to get out of the claim).
The only "inexpensive" way around it is to use UL listed interfaces made by a third party, then interface with those. But there, you don't usually get everything you want.
Of course at that point, the insurance company might just shift the burden on you to "So, did you have this done by a licensed electrician? Where is your inspection report?"...