If you like caramel malts, then use them. Personally I don't really fancy them all that much, so I try to stick with some kind of "interesting" base malt (pearl, marris, etc) and then add some character by either using a longer boil or some other malt like vienna or amber or whatever. Sometimes - and this is rare - I'll throw in a few oz. of a high crystal malt (like 120) for colour and a touch of differentiation. Just dont' be shy with your hops.
Just made a cascade SMaSH on Saturday with the following, and it's smelling AMAZING down in the dark depths of the basement:
10# pearl
2oz cascade - 60
1oz cascade - 10
1oz cascade - 0
1oz cascade - dry for 5
toss in a packet of notty, mashed at 154, and away we go!
5.2 gallons, OG 1.050, FG 1.013, 4.85%ABV (72% efficiency), 44IBU
Should be damn good, if not delicious. Beauty of a SMaSH is that you can't really screw it up. Just use hops that you like, and lots of 'em! The purpose of this one was to see just how different pearl malt is compared to plain old two-row. Since I already know what a cascade 2-row beer tastes like, this should be both satisfying and educational.