I have the J4125 based minisforum PC from Amazon and a mechanical keyboard from Aliexpress. I currently use my TV as a display and use it as a media and entertainment PC. I accidentally broke the internal tape antenna for WiFi after taking it apart several times, so I drilled holes in the enclosure and added connectors for external antennas (u.fl to SMA). WiFi and BLE work again.

I also have the display. It's an 8.7 inch display for the Galaxy Tab A7 lite. I like that size and the price for a 720p display. It uses the MIPI DSI protocol. I'm currently looking for schematics and pinouts for the display so I can design a board. I also bought another MIPI DSI display with included HDMI board. I might use that as a reference.