Oh nice! Yeah this is 100% the best way to go. I use the app Mihon for finding/reading manga, its basically the same as tachiyomi before it got shut down.

The one I use is the Boox 7.8" Nova Air2 eReader. I chose one without a color screen. The color screens are cool and all, but for black and white content, the color layer makes the white more of a grey color. For that reason I don't recommend the color e ink quite yet.

The 7.8" screen is literally the perfect size for manga. It feels perfect.

Good luck!