Mostly a good guide but I differ with you on a few things.
1. I don't know why anyone would play in FP mode. Yes, you might have a bit more accuracy, but the amount of times I can sneak up on an xbowman while they reload is pathetic. In 3rd person, you have a good chance to see what is behind you. Honestly, I've tried both types for aiming, and if you just aim a bit above where you want to shoot in 3rd Person (without rain) then the bolt will go straight.
2. Saying that the best melee option for a xbower is a 1slot 2hander isn't true imo. There are a ton of great 1h weapons out there, all of which are incredibly deadly. Elite Scimitar, Long Espada, Italian Sword, Military Pick, Steel Pick, Iberian Mace, and the Arab Cav Sword are some I have used and found success with. However, for melee the xbows greatest asset is shotgunning then back-peddle/outranging. You must be competent at blocking to have some of these shorter 1h weapons.
3. Your "Sniper" build is off. Or maybe I read it incorrectly. 15-24 with 160 wpf is useless. Being that precise wont matter with some idiot dodging all over, and shooting at a still target is easy with less wpf.
In my experience, (2 gens) an 18-21 build is the simpler and more effective way to go. You get 3IF, 6 PS, 7ATH, and 7 WM. 140 Xbow and 100-120 1h WPF.
Fast, and deadly from range and melee. Footwork powers this build.
On the whole though, a good beginner guide and I applaud your efforts for writing it.
But xbow in Europe may be different than in NA.