Different Streaming Devices Question

Well, since this is a Roku forum, any answers are going to be skewed in that direction. But my response is, it depends on what you need to stream. If you're only looking to stream from the major Internet services (Netflix, Prime Video, MAX, Hulu, etc.) you really shouldn't have any problem with any of them. If you watch YouTube and like HDR content, then you do not want an Android based streaming player, such as the Nvidia Shield. They don't support HDR on that platform at this time. Roku 4K devices will stream YouTube HDR content. 

If you want to watch any local media, and by that I mean you have ripped a DVD or Blu Ray, or have your own content you create, a Roku becomes a bit more problematic. Roku devices will not play all types of media files, so if you have your own media, you need to either ensure the media is in a supported format or use a media server that can stream the unsupported media in a supported form. This is what is called Transcoding. Plex and Emby offers a free media server that you can install on a computer and stream to a Roku without needing to worry about if the media is supported. But if transcoding is necessary the computer does need to have a bit or power. Nothing extreme, but an older cast-off computer may or may not be up to the task. 

Roku has more content than any other streaming device, in my opinion. Much of it is free, with the requirement to watch ads for the content. Roku themselves offer The Roku Channel, which is filled with free content. Any Roku other than the lowest cost Express should have dual band WiFi. If you have a display that supports Dolby Vision, Roku has several models that can stream it.

If you have a lot of local media content, you would be better off with an Android based player, such as the Nvidia Shield. These players will play almost anything without needing transcoding, show captions from almost any format, and in some cases will provide a Gigabit Ethernet connection (which would only really be needed for local UHD content).  

I have no complaints with the Amazon Fire TV line of players. What I don't like is the Amazon-centric user interface. I have no experience with the Apple TV player, and have no complaints other than the price and some limitations is has on local content. Some people don't like being locked into the Apple universe with their devices. 

Again, what would work best for you is wholly dependent on your needs, as well as your budget. Most likely any Roku (other than the basic Express) would likely do everything you're looking for. If a wired network connection is something you desire, your choices are limited with any brand. Only one Roku player (Ultra) has a wired connection, but several other players do support using a USB network adapter. Same with the Fire TV, adapters only. And I think the Apple TV is the same, adapters only.