Divingbiker's suggestion sounds good.

So you ride about 3,000 miles per year- that's a lot, but not a huge amount of distance riding. I imagine in Chile you might be doing some pretty hilly riding too?
If I were in your position, I would definitely consider the aluminum bikes. Yes they will help you climb hills because of their light weight. And the money difference is nothing to sneeze at. With the savings, you can get a higher level of components which will mean smoother shifting, etc.
The only reason to hesitate on the aluminum is if you like to do really long rides of over 150 km maybe, or if you like to ride multi-day tours. Then again some people do all that on aluminum bikes with no problems.
Go test ride a couple!