I have used both the Roku and Firestick, as well as HTPC. I prefer the ease of use with the Firestick 4k and TVs. Any form of navigation quickly takes you where you wants to go with voice control, or simply by scrolling down. With prime, and IMDB tv you have tons of shows to watch. That replaces much of the above screen you posted.
Using voice to open any app your using or show is very easy and responsive. I also like that you can side load tons of apps from android. Plex, a popular streaming content app, works very well with Firestick at many different resolutions.
The sound may not be perfect or at the level of Atmos, you can at least tinker with the Fire OS to make it work for you. And that is really nice. I prefer my HTPC for high-end uses, but everything else, the firestick, Firetv OS works very well for me.