Mine has to be Dragon Quest: Rocket Slime, a DS spin off of the Dragon Quest series that sees you playing as a slime operating a tank and rescuing the people from your town. You run around the overworld, collecting items to use as ammunition and saving money to upgrade your tank. The art and music are just as great as you’d expect from the Dragon Quest series. It made fantastic use of the DS’s dual screens. It’s also written for a younger audience, so a lot of it is just really silly and fun! Try it out for sure, I’m so sad there’s no sequel :(
I really loved a game called Guns of Icarus (the original one). Fun little airship defense game, where you had to manage fighting air pirates, repairing your ship, and saving your cargo. Extremely simple, basically a tech demo, but the aesthetic, music, and general feel were perfect. Very melancholy world that I still revisit sometimes.
Honestly guns of Icarus online was great and I had tons of fun but it never quite caught on long enough for big development help or sizeable playerbase