It really pisses me off since one of the things I loved about the Switch carts at launch was that there were no mandatory installs when you insert a game. On the PS4 and Xbox One, you have to install the full game on your hard drive even if you bought physical. And yet we're still getting them anyway on the Switch from 3rd parties.
It can't be a question of capacity, can it? I mean with technology as it is, it seems hard to believe anything couldn't fit on those carts.
I was a bit disappointed to find out that the Switch wouldn't have a mechanism for patching their own carts. Imagine being able to buy DLC and just... having it on the same original cart you bought the game on. That could have been like a new golden age for the end user and game collectors. Maybe there are so many reasons that wouldn't work, but it seemed like such a good idea. I don't mind expansions but I know I'm not the only one who appreciates a time when you only have to buy a game once to have all of the content available for it, in one place, without having to wait an extended period of time just to buy some complete edition.
As to hand-drawn stuff I'll admit there seem to be very VERY few games that have actually pulled it off, but I always assumed that was for lack of effort. I dunno. I think for me it's just a consistency thing. I like Rayman Legends visually though; I think that's on the higher end of what I think you're talking about. When you say Newgrounds flash I'm immediately thinking of 20XX.