You should've added another category to allow one to vote that neither was better over the other. Both would rank about the same for me. For Rugrats, the earlier episodes were better, especially where Chuckie's character was concerned. In the beginning, it was pretty much implied that he was older than Tommy, Phil, and Lil (who were all one). He was two. He even had a full mouth of teeth; typical for two and three year olds. As the show went on, though, it seems that Chuckie was forced to be with the "babies" of the group as opposed to the toddlers (Angelica and Suzie). This was just a pet peeve of mine. I also hated the way they seemed to over emphasize Chuckie's being scared of everything and always relying on Tommy. This was my main gripe with Rugrats. Oh, I also hated the fact that after a while, Deedee didn't even seem to have a job anymore.
As for All Grown Up, I liked it for what it was, but, didn't care for the earlier episodes much at all, and preferred the later ones. I liked the fact that Tommy was taken down a few notches compared to original Rugrats. I like how the twins grew personalities to show that they aren't exactly the same. Lil is a bit tomboyish, not "disgusting", like her counterpart, and how she's "mature" compared to Phil, who's still playful, dirty, etc., and in a way, innocent (okay, I'm pushing this one lol)
I liked Kimi and Dil way more for AGU than I ever did for Rugrats. I loved Dil's "out there" theories and unique personality. I like Kimi's outspoken personality and wish I could see that episode where she speaks out against Angelica to the school, even though Chuckie is siding with Angelica.
I like the fact that Chuckie wasn't scared of everything like the later Rugrats eps seemed to do constantly (which I found annoying) and had him let go of his security blanket (Tommy). I also liked the fact that, for the later episodes, Chuckie didn't seem to be in the same classes as Tommy and the others and for the standardized test that the others were studying for, Chuckie mentioned how tough it was when he took it the previous year which indicates that he's a year older than Tommy, Phil, Lil, and Kimi, but, a year under Suzie, Angelica, and Harold. I also liked the Angelica and Chuckie interactions that original Rugrats didn't seem to have like AGU did.
The main thing I did dislike about AGU, was Suzie's character. I really hated the fact that they were somewhat stereotyping her. She's black, therefore, she can "sing", so let's try to have nearly every episode dealing with her, reference her singing in some way or form. That got old really quick, and if it's not singing, it's something school related, which isn't too bad a thing.