More than anything, I think Swordfighter mode could and should've been cut entirely. It's a needless distraction and dilution of the ostensible highlight of the game, a Zelda-starring yarn with her own distinct ability set; having a tacked-on Link transformation to lean on shifts the entire game away from her in both mechanics and narrative framing. There is its obvious immediacy and power in just having a sword button, which ends up casting anything Zelda can do even at the peak of her respective powers as inferior to what Link can at a base level. It flattens boss design especially, where almost every single one operates on an exposed weak point basis, and in those windows of opportunity Swordfighter transformation and just hacking away is always the most efficient, optimal answer. It looms over the entire game in this way, where all the tricky combat encounters that might occur can always be solved by spending just a little bit of meter and doing away with them in the customary Link fashion, if opted for. I resented the mechanic so I rarely did so, but always knew it was there, reminding me of Link's existence. And that's really the especially stinging part of the transaction, where it's not even a case of Zelda having access to a sword, bow and bombs as more traditional, immediate options: it's that she has to literally become Link to even be able to make use of them, how just existing as "Link" is treated as a world-busting super mode, and how the entire game is spent on powering up his tools, returning them to him, and then marveling at the way he disposes of enemies largely much more impactfully than the player as Zelda can in the final co-op segment. It's "Zelda's story" in which the game is constantly asking "where's Link" and insisting through semiotics in iconography and mechanical texture on his presence even when he's supposed to be largely absent, and by the end of it ending up feeling like Zelda's a supporting cast member in her own narrative.
The dungeon design is very conflicting. On a room-by-room basis, there's a lot of fun to be had in the individual layouts, but as dungeon-spanning floorplans and the play structure they create, they are simplistic bores. Nearly every one consists of pure forward momentum with very little or none at all in the way of backtracking or navigating space in an exploratory fashion--it's probably impossible to get lost in any one of them. The few dungeons that have multiple entrances--Gerudo, Faron region--have some pretense of more involved, mazelike design, but it's never something that holds or defines the way one charts these interiors. I can only conjecture that managing all the permutations in which Echoes can interact with the environment and puzzles reduced the time and attention able to be dedicated to dungeon design that could have pursued multi-tiered, room-spanning interactions... or perhaps that's just not to this team's taste and interest, who knows. Whatever the cause, the end result is strikingly uninteresting.
The framerate issues are truly intrusive in ways that I'm often not that sensitive to. It's a game that targets 60fps but practically almost never maintains it, erratically seesawing between it and 30fps as any performance drop at all results in the game halving its framerate. For a game that involves a giant map through which freeform movement is the order of the day, the fluctuations are ever-present and significantly colour the visual presentation of the game as an inconsistent illustrator.