If price is not a factor, the best Android TV device is currently the Nvidia Shield TV Pro.
Much as I love my TiVo, it's not an Android TV box. In fact, my Roamio is a lousy streamer. It has the biggie services, but it struggles with them. Go with the Shield.
If you can wait 2 - 3 weeks, Best for the price paid will likely be the TiVo Stream 4K:
TiVo Peanut remotes are the best ones going around IMHO.
https://blog.tivo.com/tivo-stream-4k/heres-everything-you-need-to-know-about-tivo-stream-4k/
The new Verizon Stream TV is good as well. Also the Air TV Mini.
All those have more powerful AMLogic S905Y2 or X2 chipsets in them. Snappier vs the old 2016 era Mi Box and Jetstream 4K Ultra.
The 2019 Nvidia Shield Pro / Tube are the ultimate Android TV devices you can buy.
Rumour of Android TV dongle coming from Google either before May or if it then, it will happen at their "made by Google" event later this year. If you are ok to wait, wait for that.
If you want to play gaming and so on, shield tv is the better option.
If you just want to stream your usual streaming services, the mi box s is sufficient and will save you money
I want to recommend Chromecast ultra, but I need a physical remote and I want to interact with the tv. Also, Android TV like shield tv and mi box gives you built in Chromecast features