The Rachel Tommy dated is in fact Rachel Berry.Wouldn't be too farfetched, considering that she's Jewish and she was never given a proper last name (or established beyond being Tommy's girlfriend) in AGU. Given how caring she is, it's possible that from "All Broken Up" to "Pilot" she Took a Level in Jerkass. This would imply that Rugrats and Glee take place in the same universe — going by this, "This World is Something New to Me" suddenly starts making more sense.
If this gets brought back over Rugrats, it will focus on the kids in college or high school.It will do another timeskip and introduce the cast as college students or in high school. A lot of the people who watched this and Rugrats are now grown adults and likely have kids of their own by now, so a college or adult cast wouldn't be too far fetched.