I have to put in a good word for aluminum. I know people talk about how it's a stiffer ride, but I don't notice a difference in comfort (though mine does have a carbon fork and rear wheel stay). And I could afford it a pretty good quality aluminum bike with decent components. And I couldn't have afforded a Luna or a carbon bike.

When you're looking at road bikes, try a variety in your price range, and if your price range includes aluminum, don't be afraid to give those a try, too.

(How much does proper tire inflation change the feel of a ride compared to steel vs aluminum?)