[E30toF30]

As you mentioned, the caad10 is probably one of the best aluminum frame road bikes out there. If you were to compare that frame with an entry level carbon frame where both have all the same components, there is a very good chance that the caad10 will still be quite a few lbs lighter!

Im not sure any of the carbon frame bikes within that price range you are looking at (retail or cl pricing) is going to be better. Ultimately, a top end aluminum frame will almost always be lighter than any low end carbon frame from any company. Those are my thoughts on the weight side of things.

For geometry, you won't be able to have both super stiff, fast and comfortable all in one. At least I don't think so. You are either going to get something with shorter wheelbase and stiffer which gives you more responsiveness (more twitchy even) and faster, or something slightly longer, less twitchy and less stiff, but more comfortable for the longer rides. Pick one that will be most suitable for your typical rides. If you are racing then go with the faster stiffer frame. If you are going to be doing 100-200km rides, maybe opt for the less fast, more comfortable frame.

At the end of the day it doesn't sound like you are doing any racing so the differences between the different frames won't matter much at all. So my suggestion is get what is most comfortable.

As for other options, I also love Giant. My last three frames were all from the TCR line, as is my current. I find that Giant bikes offer way more value compared to other brands like specialized and cannondale. The same spec'd components on a similarly classed frame is typically a few hundred bucks less at minimum. Not to mention, Giant is one of the largest frame manufacturers (if not the largest) in the world and they make some pretty badass bikes!

Gl on your search on please share pictures when you pick up whichever bike you decide to go with!