Different philosophy.
Ntfy uses pub-sub like MQTT. It publishes messages and anyone (with access) can subscribe to it. Want to connect 250 clients across 50 people to have the same messages delivered? Easy.
Gotify uses end to end messaging. A user creates an application on their chosen client. Gotify uses a REST api send the notification pulled from the chosen app to the user who made it. Want to do the same as above? You have to set it up 250 times. Gotify was the first to have authentication and some people say it is more robust, but I can’t speak on that. Also gotify is easier to set up and makes sense for a single user.
Someone can correct me if I am wrong, but that is the biggest architectural difference.
It really really depends on what you have for heating.
Floor heating + heat pump? You don’t need to mess around with target temp much because the principle behind it is thermal mass buildup and maintaining that. You have to tune thermostatic valves on the room level. Then you can have one central thermostat simply slightly change the target temperature with many hours of delay. That doesn’t seem too useful to me to automate.
Do you have radiators? Then you can get zwave or ZigBee valves and tie them together with whatever thermostat that you want in home assistant. Then you can set per room/zone heat depending on whatever sensors you have.
Do you have central forced air heating and air conditioning? Then you have pretty much target temp and on/off control unless you want to put in motorized automatic registers or redesign your entire duct system for per-room duct valves.
Individual heat pumps/airco units with radiator based heating is the most “per room” customizable and probably the most useful to put automations on in Home Assistant.
Ventilation can be useful by monitoring CO2 levels and humidity. Then you can use either the fan units themselves or socket switches to actuate those and put whatever sensors you want wherever it is useful.
I am probably missing some stuff here, but there are only a few HVAC setups that actually benefit from automation, in my opinion. Mainly ventilation, infrared, and non centralized forced air heat pumps. Plus heating and cooling is something you want to work 100% flawlessly even if your router dies, your home assistant falls off a cliff, and your ZigBee/zwave controller dies.