Another thing to consider with that type of vehicle is the suspension, tires, and brakes. The items they use on the Lexus are sure to be geared toward comfort. I would start to worry about what would happen in an emergency stopping situation.
I've got a 236LS which is probably a little lighter than your 230CCR. I towed it to Cumberland with our Tahoe and it just wasn't something I enjoyed doing. The tires were the biggest issue and anytime a semi would blow by the boat would wag that Tahoe like crazy.
With an SUV you load alot of weight into the back with coolers, gear, etc and then the tongue weight of the boat. That's alot of weight sitting on those dinky sidewall tires and rear supsension.
I'm not saying you need a 3/4 ton pickup but I upgraded to an F250 in November of 2006 and love the difference. I agree with Mike that if you're doing mostly local towing you should be "OK" but I would go and get your trailer and boat weighed so you have a better idea of where you are sitting for weight.