Racketboy has compiled a list of five different Metroid games that would be fine in 2D, just like the old days of Metroid being on the GBA.
List is in the source.
Some established franchises just feel more natural in 2D. Even though I love the Metroid Prime series, I still long for the polished 2D gameplay of the earlier installments. Just for fun, I wanted to think about five different projects or ideas that would suit Nintendo just fine in filling the 2D drought that we have experienced since the GBA Metroids. If you have more ideas, Id love to hear them