You still haven't' said what you want out of this bike, other than 'aesthetics' We're trying to give you some guidance, but it's difficult with the only criteria so far is a unicorn XL frame that you like the look of, but haven't found yet.

Is it a particular color scheme? Frame geometry? Graphics, or lack thereof?
It's easy to change the color of a bike; you just paint it. Stripping and re-assembly will give you a good feel for how it goes together.

Where you want to end up will be a key factor in where you start. 29" or 27.5" wheels? 1x11 or 3x8? Hardtail XC or Full Suspension/Freeride? Alloy or Carbon? If you don't know where you want to end up, it's hard to help you get there.

You said you liked the Giant Talon 3 It's available as a 2017 model, and still black w/ green. List on it is under $600. I understand the desire to build it exactly the way you want, but you could easily spend a grand to build that exact bike a piece at a time.