1. Like you said, durability is fine and essential if they are going to continue to have a large weapon variety, but it needs to be tweaked. Some kind of indicator that is easy to see (like minecraft weapons for example) would be nice. Overall weapons should last longer than they do in BOTW, and not be so commonly equipped by enemies - so when you get one in a chest you actually feel like it's a reward. Late-game weapons should be able to be repaired a-la crafting.
2. Crafting. Cooking is one of the best parts about BOTW (imo, and should be slightly nerfed to give less hearts) because it calls on the player to scavenge the world around them. Crafting would expand upon that idea and make exploration more rewarding. One of the things that bothered me so much about the early-game in BOTW was so hard it was to get arrows, especially without buying them. Allow us to craft arrows, for example, with wood and ores. Or make a tent with the hide of an animal to escape the cold or hide from monsters. Or high level weapons with rare metals that can only be found in remote areas of the world, etc etc. The crafting should be simple and accessible like cooking is in BOTW as well.
3. Dungeons. The highest priority of the next title. The beasts were a unique departure but never scratched the dungeon itch. I want majestic imposing dungeons that you can see from miles away, but are a challenge to get into like in ALBW. And also like the beasts, I want to at least be able to look upon the outside world from the dungeons to feel like they are blended. Memorable music needs to make a comeback here as well.
Dungeons should become semi-linear. Have a set of 2 or 3 dungeons, each of which give you a new item and can be done in any order, then have 2 or 3 more dungeons which require all items from the previous set; this allows for greater complexity in design.
Which brings me to my next point...
4. Items. Runes straight up need to go, as the harm they caused to the progression in BOTW was not worth the freedom. The best runes should be repurposed into new items (Magnesis, Stasis) and bombs can just get their classic appearance back - and require stock like arrows. Each dungeon would reward you with a new item, just like classic Zelda. Give us secret items too that can only be found through side quests, etc.
5. Shrines. I like the concept but they should go away in their current form. Instead, it would be cool if they revamped the idea as "trials". The trials should all be integrated into the world - they can be just like shrine quests (Eventide island was a great example), or hopefully expanded upon into things like mini-dungeons, or arenas where you need to kill mobs of enemies. Give us graveyards infested with re-deads we need to clear out, or random caves in the side of a mountain filled with puzzles. Trials should look natural, not stick out like a sore-thumb like shrines. The rewards could be the same since I don't really have an idea on what else the rewards could be.
6. Enemy variety. This is probably the second biggest one after dungeons. Not much needs to be said here, other than there is a plethora of past Zelda monsters that need to return. Deku babas, darknuts, redeads, etc etc. Most importantly, locations need to have unique enemies, there shouldn't be any other monster besides bokoblins and keese that you see everywhere.
7. Story and voice acting. I like what they tried with the memories, and wouldn't mind that returning, but it should be saved for additional storytelling, not the only device used. I want a Zant-like miniboss/ big narrative points that aren't just optionally skipped. Or a huge battle over Hyrule field involving an army of monsters. And yeah voice acting needs major improvement, they really dropped the ball there (which is fine because it's the first VA Zelda, I guess). Every character needs VA too not just big ones in cutscenes.