My main experience with heat pumps is a heat pump installed in the northern US in the mid 1990's.
As a user, the main problem is it's fine in spring and fall, but:
- (1) In winter (when the temperature is below freezing) it can't keep up, and needs to switch the gas furnace on
- (2) It often needs to be manually switched at the thermostat, you should be able to interface an outside thermometer and say "below X degrees use the gas furnace"
- (3) The homeowner told me that they'd never have bought a heat pump if they'd known it would only work for like 25% of the year. Decades have passed, so presumably you have better tech. But you need marketing and customer education to explain that it's better, and assure your customers that past bad experiences aren't indicative of future results if they buy your system. For me, that means performance metrics (e.g. curves for various house sizes showing the duty cycle needed to maintain a given indoor temperature as a function of the outdoor temperature) and testimonials from customers in states that border Canada.
Also, you stress fighting climate change a lot. My sense is that, if you emphasize climate change, you'll potentially alienate the half of the country who thinks climate change is fake news. (As a group, homeowners who buy heat pumps are probably older and more conservative.) You have a bigger market if you stay apolitical and sell a practical product. Features and cost savings appeal to everyone; fighting climate change does not.
Your pitch is fine for HN. But for a general audience I'd either (a) leave out the references to climate change, (b) move them pretty far down (not at the end but maybe 2/3 of the way down), and/or (c) emphasize "the government wants to fight climate change and is making the following assistance available..." informing customers those financing options exist without yourself taking a position on the issue.
Also, I agree with other commenters: It's important your product will keep functioning if you go out of business or the customer stops paying a subscription fee.
For me personally it would be great to have a wifi and Ethernet enabled thermostat with an HTTP JSON-RPC endpoint that gives raw data of when the heater turns on, indoor / outdoor temperatures, and be able to change the set-point or turn the system on/off via LAN (protected by some auth mechanism). An interface to existing FOSS home automation solutions would be nice to have but not essential. The main thing for me is that your interface is open and can be run without any subscription fees or access to the cloud.
It would be a real plus if everything's open source and off-the-shelf components. Ideally if a voltage spike sets the computer on fire, I can unplug the cables, slide the board out, buy a Raspberry Pi, Arduino or similar, re-cable everything, download the software onto an SD card, and bring it back up.