Hmm,

I've never played a ToM, but unless I was a Star Wars fan, I'd probably sell the SWEP1.  I've only played it once and it didn't do a great deal for me, but neither did RFM.
T2 is always a good one to go back to and for visitors they like playing it.  TZ keep.

If your SWEP1 is minty, you could even get a B-title DMD and maybe a SS.  I've been around them (working on BH) and having a look at a MGOW, Medusa etc some of these games would compliment any line up.