For those going for 100%, how are feeling about some of the repeated content for some of the moon types?
I'm not minding it much for the most part, personally. The way Odyssey handles common objective is kind of the best way it's been done in any 3D Mario. Looking at Bianco Hills in Sunshine we can kind of see this at its worst: out of the 10 objectives, we have a sludge piranha boss battle (which is seen in almost every stage); two battles against Petey; two "secret" stages (which I won't hold against the game because they're always good, but it does show how repetitive the structure can be); a chase against Shaddow Mario (something that's done in every stage as well as in the hub multiple times); and FOUR red coin missions (also seen in varying capacities in every stage). Now, there's plenty of unique content between these objectives in Bianco Hills, but all the mission types aside from the two Petey battles are seen extensively in other levels. All it'd need is an El Piantissimo race and we'd have everything lol. And you still get this in Mario 64 with stuff like the koopa races, red coins, and most of Tall Tall Mountain which really just sees you making your way to the top of the stage a little bit more for each star you collect. Also see: the comet stars in the Galaxy games, and green stars in Galaxy 2, which just sat around and kicked you out of the level whenever you found one.
And basically, that whole not getting kicked out thing is what makes all of this mostly fine in Odyssey. Moon shards (this game's red coin equivalent), koopa races, little challenge zones, picture clues ect. let you get a moon and keep exploring, ON TOP of just being a small part of each kingdom. So even though, yeah, I do actually think there are too many moons in a lot of instances, there aren't as many that come across as straight up padding as you'd think, because these objectives don't account for 1/6 of the missions you do in a given level. The truly open nature of the levels help too, which somewhat makes up for not being able to do chunks of levels in any order you'd like.
That being said, the Lakitu fishing really upsets me haha. It's maybe the only moon type (aside from the dogs? But those kind of stink too) one that doesn't change a wink from kingdom to kingdom. And the fact that they're just fish silhouettes is plain lazy and boring, it's honestly the only thing that's felt like a chore to me. If anything is flat out busywork in this game, it's this.