Fates and Awakening are some of my favourite games of all time, I don't really want a big shake up.

I would want:

- Full supports; every character can grow to S-rank with all other playable characters. Keep the kids as well, that whole set up was one of my favourite parts of the 3DS games. Maintain the humour too, I liked seeing the characters personalities be revealed through their supports.
- Keep the battle system as it is. Like Pokemon, the heart of the game is already incredibly solid, beyond polishing, it needs no major changes.
- More customisability, let me pick outfits for characters and in doing so change their abilities (upgrading armour, as well as weapons) and have this reflected in their appearance in battle. This appeals to me more than the traditional thing FE has about all units of one class looking largely the same on the map
- I'd like another Fates-esque war between two countries story, give me the choice to just conquer another country for the sake of glory, make it morally grey.
- More side-quests. The recruit missions from Awakening/Fates were fantastic, I want more of those, as well as other quests which give a deeper look into the lore of the world and allow more insight into the characters
- A longer main story. Around 35 chapters would be great. I loved Fates, there was so much to do, with 81 chapters total through the three games. This time if they take a similar approach, I'd like them to have two games of 30 chapters each in the one package (You pick your country, and the story you play, during character creation), and they could have another similarly sized campaign as DLC.

This is kind of off-topic, but ... I fail to see how Mario Odyssey was really a shakeup, especially if you're comparing it to Breath of the Wild.

Mario Odyssey was as different as 3D Mario games usually are from eachother, I thought. If it's a shakeup, then so are Sunshine, Galaxy and 3D Land.

If anything it needs to go back to it's roots more. Awakening and Fates were grinding and breeding snore fests with really slow paced padding stories...

If the game comes out in 2018, I doubt it. Just moving to a new HD engine is a lot for Intelligent Systems, who I think have only worked on Paper Mario: Color Splash and Pushmo World in terms of HD.

But short of going full hog on a Gaiden/Shadows of Valentia style map system, I can't see FE being able to do something similar to open world, especially since they tried a project similar to that in the Wii era that was eventually scrapped for being too different from the standard formula.

My thoughts exactly. One could also argue that BOTW is just a return to Zelda 1 and 2, but it's a lot harder to see because of the intervening 30+years of evolution in gaming.

FE is fine the way it is.  Mario and Zelda went big and open, the only analogue I could thinkof would be FE doing away with the world map and connecting all the levels with each other, but I doubt that would be an improvement.