I have used Slingbox for about 8 years now. What it primarily solves is bad Internet, it adapts to slower network and presents a watchable experience. Good example locations is when on free hotel wifi and the guests are watching
Slingbox has got smaller and faster over the years.
Now you mention it.... it makes me think I may do myself a service via connecting it to the HDMI output of a Raspberry Pi type server which is running a desktop, because that could solve a few problems.
However, the ability to download media is your friend, I barely ever watch streaming media now with network hiccups, I download to offline then view from offline, it just helps through Wifi hiccups etc. All my devices have 64GB minimum storage. I am usually at 90% full and delete that 2 year old series I never had the mood to watch.
To make downloaded media work well I sometimes I post-process the media using ffmpeg to slowly shrink the MP4 without losing noticeable quality. What that means even in 64GB I'll have weeks worth of stuff with me for any situation of bored in a bad/no network.