I'm totally going to jump on the pile, and say that building your first bike from scratch, especially since it looks like your buying all new parts, at retail, will be a good way to spend $1000 to build a $700 bike.

The way that builds turn out the best, is as someone said, if you have a really specific set of requirements, or a 'signature' component to plan the build around. Otherwise, your'e just swinging in the dark.

An 'endurance road bike' is a pretty non-specific requirement. I can go on my local CL and find a handful of Cannondale Synapse, ready to roll, from $600 for an AL 105 rim brake, carbon 105 for $800, and a 1-yo AL 105 disk-brake for $1000.
How do you plan to improve on something like that?

There's a bunch of 'I want to build a bike' threads in here that ended up with kludged-together bikes, or frustrated builders who fell down a rabbit hole that took way more time and/or money to get out of than they were willing to spend.

Larsbb's build thread is a good example of how a successful from-scratch build works. In his case he had a very specific design brief; belt-drive, single-speed, city bike. Even still, he ran in to a couple of snags, and put him (he admits) way over budget, even on a very simple bike.