Sadly, the originals are only done to be printed at a maximum of 4"x6". I started them mainly as practice in SAI, and then they became ridiculously popular! I'd love to get them printed as postcards, and I was trying to make a poster with all the main figures in it, but I stalled out trying to figure out a background. ^_^;
I have *really* thought about re-doing them at a larger size... 11x17, or thereabouts. Right now I just have no time. x_x My video game project is starting to pick up, so I'm working like crazy on that, but maybe it's something I can work on slowly in my "free time" (haha). I'd like to be able to offer them on shirts on Redbubble, as well.
Allegedly the series addressed more and more mature themes as it went along and the characters actually grew older, since the creators planned for the target audience to mature as they followed the show.
There is definitely truth in that. The show is surprisingly deep, and *really* funny, not afraid to poke fun at itself at times, but still gets serious when it's called for. Unfortunately, it does suffer from a lot of the problems that anime from that time is known for; lots of filler, inconsistent quality due to low budget and multiple animation teams, lots of recycled animation. But it's worth watching if you have the time to go through a 200 episode series. Just don't watch the English dub, it's more dumbed-down than any of the other versions.