ᐅ Opinions on Our Home Design

Hello everyone,
we plan to start building our house within the next 2-3 years.
The location is about 20km (12 miles) west of Innsbruck in Tyrol. The plot is on a gentle slope. The house is planned for 2 adults and 2 children.

I apologize in advance. This is the very first step towards building our house. Of course, we have already researched and have some ideas, but we are not professionals. Our thoughts are still in the early stages and certainly have room for improvement, which is exactly why I’m here: I want to receive both positive and negative feedback as early as possible to design the best possible home for us.

A brief explanation of the attached image: Based on the initial information about the room layout and legal requirements, the sketch below is a first draft of the initial ideas. It was drawn with the limited tools I have available. The street side is north and the garden faces south. Due to the slope, the garage is accessed by car through the basement level, which is at the same height as the street.

The house will mainly be constructed using prefabricated steel segments. The east, south, and west walls of the basement will serve as retaining walls appropriate for the slope. The steel frame should already be in place on the north side. The entire house should be well insulated, although we are still unsure about the exact level or “class” of insulation.
A decentralized ventilation system should be installed in the basement, living/dining area, restroom, bathrooms, and bedrooms. The reason for a decentralized system is the desire to control the temperature in each room individually, as well as to accommodate different daily routines, etc.
The bathrooms will be heated with electric underfloor heating directly beneath the tiles, so the screed does not need to be heated. All other rooms will be heated with infrared heaters.
Regarding flooring: All rooms will have “warm” floor coverings, such as hardwood floors, linoleum, or cork. Naturally, the bathrooms will be tiled, which is why underfloor heating will be installed there.
Shading is planned for the living/dining area and bedrooms.
The entire building will have home automation (heating, shading, lighting, security system, etc.). Before anyone objects: I will try to do as much of this myself as possible. I have experience from my training with home automation and am a certified KNX installer. However, I plan to use Z-Wave as the standard in the house. The idea is to only heat rooms that are in occasional use minimally, for example, the multi-purpose/hobby room. Bathrooms will only be heated in the morning or evening, and only when someone is at home, etc., thereby saving energy.
Because a planned electric car and the heating system will result in significant electricity consumption, a 15kWp photovoltaic system is planned. The energy consumption will also benefit from a lighting concept using 100% LEDs. The current electricity price is about 14 cents/kWh, which is relatively low. For higher energy demands, there are alternative providers offering a higher fixed fee but a lower price per kWh. The plan is to switch providers if needed.

Please be patient with me. I’m not inventing these ideas myself; I have picked them up somewhere and they seemed logical and useful to me. In our region, these topics are quite unusual, so there is little local experience. That’s why I’m turning to the forum.

I hope you will help me develop our ideas.