I am looking to set up a media centre in my living room. I am looking for the following functions:

Light internet browsing

Legal free streaming (youtube...etc)

Access to NAS and play as many formats as possible (I have files from 20 years ago and would be great if I can still play them)

Supporting 4k is not important 

I search around and think I have 3 options:

Raspberry Pi 4 - All up around $200

Android TV box - varies - possibly a mi box S ($130) to a Vodafone TV ($179)? Open for other options

mini/stick PC - varies - between $200-$300

I am not looking to spend more than $300 on this project.

Is there an obvious route I should be going? Thanks.