I just used a mini PC with kde and this remote keyboard.
With kde you can set things up pretty good. There’s a lot of possibilities. I never had casting set up though.
A mix between Kodi, and stremio.
It worked good for steam link too.
I tried with a raspberry pi but it was slow. I wouldn’t recommend it. Idk how others are able to use them. Omsc or whatever might be okay.
I don’t recommend this one with kde desktop Not sure how it is with big screen.
This one is great for general PC use. https://www.amazon.com/Rii-Bluetooth-Keyboard-Smartphones-Mac-Black/dp/B07T13GLY3/ref=mp_s_a_1_14?crid=2WE5IDKRXKGV4&dib=eyJ2IjoiMSJ9.xrnVtYYFTyO73ZuMPlMTiXuUtrXgu563ShL0RpC2E6Xc7hns3f8uHG9GfZK7BoKuBAEB5ZCWdZXwPPRdNcLbOs5WitdHNrWgJlJZMZAo4OIELITXPEAqZJzbeYRZxnwpfgkBsiU947VEBWvtTAkj8UTRRFynHFwOKXdF5VgSU8UlPR5RePsuUUndFEpOtHOCSCDJYTyLj56yx3VQfNQDfA.D7Rgpcdgj4ltPso9vVwL3X5B9bY1c8IRphOPAebVH1Y&dib_tag=se&keywords=mini+keyboard+with+touchpad&qid=1725323885&sprefix=mini+keyboard+%2Caps%2C169&sr=8-14
If you are looking to clone TV remote IR buttons there is this one. The orange buttons can clone TV remote buttons. https://www.amazon.com/Rii-Wireless-Keyboard-Touchpad-Controller/dp/B0C5LFLL3G/ref=mp_s_a_1_1_pp?crid=247JUEQKDFAAL&dib=eyJ2IjoiMSJ9.J1g9QtAF8xB3mG5ZS6etrWUR8cxrIbmY-Oit0UosNDdx9GOe4HOH-SC-IgSIymfthR7fZA7_WdoiGNPvKqQzpXxYvOVi4cy7zqdiaK3qTTq8s5T7F8mWjjIICmOJFabGJAaYknW4Yo82sn18O3n_Vb2D-E0LQYl7qgUqoUcAJd07BoTIgZTmgvqsqWl_3clD0sbzKhjFKfDdixiRLuBCSw.5mMB6rANHKQtxt1qbEeHzMvBxR3Rep5-BBOJFQlMZZs&dib_tag=se&keywords=rii&qid=1725324362&sprefix=rii%2Caps%2C127&sr=8-1
If you are going to use a PC desktop (kde is great) I recommend getting one with the scroll wheel.