I think you will like a road bike better. To save some coin and possibly get a better bike for the money I would look for something that is a year or two old on Craigslist or New old stock at your LBS that you can save money on. Rim brakes are a bit lighter if you are not set on disc.

If you do buy on Craigslist its important to know your size. No bike is a good deal if it doesn't fit you

I would look for a used Caad 10, Spec. Allez or a Defy if you are set on Aluminum.

Hope that helps!