Ethan Embry who played Rusty has been in quite a few movies (Can't Hardly Wait, Empire Records, That Thing You Do, Harold & Kumar etc)...As for the "family truckster" yeah I don't think it was used past the first movie, but I have seen it pop up in various other films around that time (same color scheme and everything).

And, South Park, of course. Chef's car.

I think the kids in this movie were pretty good. The only "Vacation" movie I did not watch in entirety was Christmas, so I can't speak on those kids. I like how they play on the different kids though: "You kids are growing up so fast, I hardly recognize you!" So I think they are good at making fun of having different kids for every movie. Ethan Embry was great here, going from what seemed like a goofy kid to Mr. Papagiorgio, playboy and man about town. "Having an entourage is expensive!" Marisol Nichols, the only other thing I remember her in was "The Princess and the Marine" where she plays part of the royal family of Bahrain and sneaks out of the country to marry a marine. Okay acting, but nothing really Oscar worthy.