Hi there-

You are definitely doing all the right homework! And getting out and RIDING bikes, most importantly. I could offer a few suggestions that would take priority for me, personally.
1- carbon DOES make a difference. If a full carbon frame is out of your price range, consider a bike w/a carbon fork, consider buying a 2nd hand higher level bike, or consider upping your price! It may be a sacrifice now, but you will be loving this bike for many years to come.
2- at your height, you could do a WSD frame. This is more of an issue for women with smaller hands, shorter torso/leg length. etc. I am 5'6" and find WSD frames don't fit me well. And -- manufacturers will sometimes skimp on the components for similar models when offering a WSD vs. standard. At least that was the case when I was researching this a year ago with TREK.
3- at 1000-1500 you are probably looking at Shimano 105, maybe some Ultegra. I would go the extra yard to get the Ultegra. You won't regret it!

I hope this helps. Good luck!