I'd definitely like to see more modern cars kitted. I was born in '70, grew up in the '70s-80s...have loads of kits of '60s-70s subjects that I like...the '50s and older are too far before my time to be of much interest to me..have kits of some cars from before the '60s, but it's not my main area of interest.
Reissues of '70s-80s subjects are welcome by me, that was the era I started building kits (1978, to be exact). Alas, many of the interesting cars of the late '70s were never kitted (like the '77-79 Caprice, '76-77 Cutlass Supreme, etc).
Lots of modern subjects would be great in 1:25th or 1:24th scale beyond the usual Camaro/Corvette/Mustang/Challenger subjects---I'd like to see the new Charger and Chrysler 300, Ram truck, Ford Raptor, Cadillac CTS (esp. the V-series coupe or wagon), the new '12 Porsche 911, other current Porsches like the Boxster Spyder, GTS or Turbo, the Audi A4/S4 and A5/S5, A8, various Mercedes sedans and coupes (esp. the AMG versions), the current BMW Z4, M3, M5, etc. There are lots of interesting modern subjects that could be kitted.
I'd like to have kits of modern SUVs also...the current Grand Cherokee, Wrangler, Tahoe or Yukon, as well as the Cayenne, Escalade, etc would be interesting in kit form.