As fun as it would be to see several different cross-overs, the only one that really makes sense for me, and be realistically do-able, would be Criminal Minds. They, as the FBI, travel the country, so they could go to Vegas and interact with the whole team, plus we know Vegas has a field office. The biggest difference I see is that CM focuses on behavior while CSI is forensics, but maybe they could still swing it.
As much as I love both NCIS's, I'm having a hard time thinking of any Naval cases that could take place in Vegas, lol. Maybe I'm just not creative enough.
On a CSI multi crossover, my favorite idea would be with NY again, but only if there was a way to make all of our cast involved, not just one person like the last time they tried. The spin off pilots worked pretty well in the beginning, as they introduced most of the casts, but the ones with only Ray going to Miami and NY just sucked, imo.
Watching the 2010 cross-over as a NY fan was ok, although even then there wasn't enough of the rest of the cast featured, with the exception of Mac and Ray of course. As a Nick fan, the first two sucked until it ended in Vegas :lol: