Nah, not really. Substitute Ross Noble with one of the following, and you've got it: Jo Brand, Phill Jupitus, Bill Bailey, Rich Hall, or Jimmy Carr. You really need one of the QI Vets to be able to set up Clarkson.
It's rather surprising that the crossover list between QI and SIARPC is as small as it is. Just going off the Wikipedo list of QI guests and SIARPCers, it's only the following: Stephen Fry, Alan Davies (gotta start with them), Jeremy (duh), Bill Bailey, Rich Hall, Jimmy Carr, Rob Brydon, Johnny Vegas, Rory Bremner, Eddie Izzard, David Tennant, and Terry Wogan. I'd kill to see Jo Brand do SIARPC, just to see her discussion with Jeremy beforehand.
