Signature really is the "mellow" hotel over there in MGM-world. It's marketed as business-traveler-friendly and probably low tolerance for rowdiness. People book there specifically because it has no casino. Probably not the best place to go whooping it up--- even if no one complains, that's incredibly rude to disturb the guests who specifically picked a "not-Partiers-friendly" hotel by having a loud crazy party.
Have you looked at the other MGM hotels: NYNY and Monte Carlo cater to a young crowd but aren't generally as skanky as Luxor has become. Unfortunately they're often pricey when MGM is full. Excalibur tends o be cheapest of the MGM family but may be too downscale if you're considering MGM/Signature.
You are right that the Palms will be quite remote.