I actually have a lot of thoughts about Pikmin 3 lol—I like it quite a bit but it is by far my least favorite in the series, and the relatively minor changes in the Deluxe version take things even further in the wrong direction.
The first two games had fairly imprecise controls, weird & difficult-to-understand enemies, mostly-nonlinear levels, and interesting collectibles that were worth seeking out for reasons other than increasing a "completion percentage".
3 places a huge focus on perfection and optimization, meaning that the level of control the player has over the Pikmin has been tightened up and enemies are simple to predict and deal with, and a new "charge" move replaces the strange C-stick rallying move to do a bunch of damage at once—Deluxe doubles down by letting you lock on and hold the button down to rapidly throw all your Pikmin (though I understand the accessibility benefits of this as opposed to requiring button mashing). Rather than a bunch of guys to wrangle and try to manage and direct, your Pikmin mostly function as A Number, an ammo count to keep maxed out and to unload on enemies or fruit—the ever-present numerical indicator next to the cursor reinforces this.
The levels in 3 are a bit open-ended, and in particular often require you to split off in a few different directions to progress, but they're so heavily focused on forward momentum and commitment to that particular level's "mission". The mission structure sidelines the collectibles that were the focus of the first two games in favor of linear progress toward a boss battle, then a move onto the next level. I actually think the fruit collectible system is really smart, but it's balanced in such a way that, arguably even in the Ultra-Spicy mode, there's no real incentive to seek any off the main path unless you're concerned with overall completion. In the first two games, almost every collectible, and thus almost any direction of exploration, is meaningful.
There's also no weird mysterious stuff like Mamuta or Goolix or the Smoky Progg or even the Waterwraith—I think strange, unpredictable stuff like that was a hallmark of games of the Gamecube era (I'll give the caveat that these were some of the first 3D games I played, so perhaps everything was mysterious then). The fact that there was rarely any dialogue within the individual days to give any context to those weirder bits (e.g. a massive ghost emerges from an egg and plows through you, instantly killing 60 Pikmin; at no point does the game stop for Olimar to say "My scanning device says that that's the Smoky Progg! Be careful, or he'll eat all your guys!") made them all the weirder and more magical.
Anyway, I'm not too worried about enjoying 4 if it ever emerges—they've mixed up the structure in each game so far, and, especially if they save it for their next platform, it'll probably be the best-looking game Nintendo's ever made. And again, I do like 3 a lot, Pikmin as a whole is probably my favorite Nintendo series, it just throws out a lot of what I loved in the first two games to make a slightly but fundamentally different kind of game.