I thought the robot rewiring puzzle was kinda fun until I got to the last puzzle. At that point, even with taking screenshots of the correct wires, it was tedious. If they let you label the pegs, or added a list of correct layouts once you found them, I think that would've turned out a lot better. It was like that in Monkey Island 4; once you figured the right combination of sounds to change stances in Monkey Kombat, they filled out a diagram for you, and you could just pick which stance to change to.
I think the issue of omnipresent information, that some puzzles are only solvable because the player learned the answer from the other character, could've been solved if they jokingly addressed it somehow in game. Just poke at the fourth wall a little bit: When Vella knows Shay's toy's name, have her joke about what a lucky guess it was and how that's a stupid name. Or when you fail at charging the robot, have Shay say he should've paid attention when his father tried to teach him the correct wiring combination when he was a kid. Or have a short cutscene play out where it's implied that he spent hours manually trying every possible combination when you solve the puzzle. As it is in game, these characters don't even comment on the fact that they somehow know these things, and I think that's the most jarring way to handle it.
And the ending was just disappointing. We barely get to see anything about Loruna, even during the credits epilogue, when that seemed like a great place to have a final showdown (I guess DF didn't want to build any new environments). Instead, we get a standstill between the two Mog ships, where Vella decides to blow them up for some reason, and Shay is forced to unknowingly go along with it? At first, I didn't even know that was the goal until I found that Shay can make his ship grab Alex's. I was just thinking "Why? Why do these two characters want to destroy the ships they're currently in?" All the dialogue points that you should look for a way around the other ship, or to stop the Loruna people from attacking you. You're given no reason to destroy these ships, aside from the fact that it's the only action you're capable of doing. And we're supposed to believe that a highly insular society will open the wall they've built to keep "the foreign plague" out and accept outside visitors, just because there's a bridge? A bridge made out of their last gene-pool saving ships after one of the visitors had just blown up their production factory? And everyone lives happily ever after. At least they didn't have Shay and Vella instantly fall in love.
And why was the grandma evil? How did she get from Sugar Bunting to Loruna before any of the other characters?