I also endorse the RPi+OSMC route. Another thing to mention about controlling Kodi [the underlying software used by things like OSMC or LibreElec] is that you can generally use any input method you prefer.
- it supports a directly connected keyboard, mouse or controller
- when using a RPi and connected to a television via HDMI, usually CEC will allow you to use your normal remote control - but if your particular TV isn't supported there's also things like Flirc you can plug into a USB port and then customize for your remote
- you can use a web browser from any computer on the network
- there's a bunch of different apps for your mobile phone. On Android the official (free) one is Kore, I prefer the extra features provided by Yatse but after migrating away from using Google Play Services I've had issues keeping the purchased "pro" features unlocked; but it's still a better experience even without them.
And it's not an either/or scenario, you can use all of the above simultaneously without changing any settings.
Some people say I'm egocentric, but enough about them.