Metroid needs to be reinvented in a way that appeals to classic fans (no death threats) and a more modern audience. Giving the franchise an action-oriented design in Other M was one attempt at this. A lot of the decisions being made in Breath of the Wild make a lot of sense if applied to Metroid: free-roaming an open world with challenges that allow the player to upgrade their health and abilities, making the game about survival and player approach, and the option to engage in the story or not.
However, I'm going to go out on a limb and say that what Metroid needs is Platinum Games. Bear with me here, because this is the first time I would ever consider letting Platinum touch a franchise I actually love- I would say that the best parts of Other M are when Samus is vaulting around and kicking ass, getting characters in headlocks and blasting the crap out of them with missiles. The boss fights in particular were pretty cinematic and thrilling. The flaws were the story elements, gating of previous areas, and the control mapping. I'd say a number of the challenges players could tackle during the limited exploration segments in order to obtain power ups were actually quite substantial, and I enjoyed a lot of them.
While boss fights are integral to Metroid, Fusion took the approach a step further and streamlined the action of the game in order to deliver a more tightly-action-oriented approach. While Platinum has a penchant for delivering on such action, they could expand on Samus' play style (and her use of projectile weapons in a similar vein to Bayonetta) with their control schemes, and maybe even experiment with non-linear progression and power up acquisition in a way they haven't in the past. The way Platinum integrates combat moves and allows them to change enemy encounters, such as those present in The Wonderful 101, Metal Gear Rising, and Bayonetta, could be a good fit for Metroid, and allow players to tackle individual runs in their own ways. Likewise, while they could have certain power ups be mandatory for unlocking newer areas and boss fights in the game, if they were to create solid combat fundamentals and have earlier bosses toy with the core mechanics of the game, it might be a great way for players to once again approach the game in their own fashion.
While it would end up combining two of the most volatile gaming communities (Metroid elitists and Platinum elitists), I think that it could be executed properly and take the best parts of Other M and improve upon them. It might even be an easier game to develop. Plus, the Metroid elitists might clash so heavily with Platinum fans that the ensuing battle would wipe both communities out and pave the way for a better future.
EDIT: I apologize if I hurt anyone's feelings about being a Platinum Games fan- however, there's a very tiny, very dedicated group of people that think Platinum make under-appreciated masterpieces and complain when their games underperform. The reason for this, of course, is that precision/mastery-based character action games aren't necessarily a hot commodity, and that, like many technical games that take time to master, they aren't what the majority of gamers out there want to play on their down-time. Team-based, technical and performance-based games are the hotter commodity.