I don't mind the Boyd's stock at all, I just don't think it's a great stock. The At-One is a poor attempt at a chassis stock and while functional it is limited. You're limited on pistol grip and forearm styles. Same with the other chassis the X-Ray 180 you linked, it is severely limited as to what you can do with it. I just think a chassis system like MDT that allows parts interchangeability is a far better option.
Also I don't think you're in over your head, but I don't think you are considering everything. The barreled action I turned you onto is $400 but you need to add probably around $35 for transfer fees, so it's now $435. The stock is $189, but it looks like they sell the extra forearm and pistol grip seperately, so you'll be over $200 for that with shipping. Next buy the DBM bottom metal and two magazines like you linked and you're in for another $120 at least plus add your rail for another $60. Now you have a total of around $810 and you'll still need to assemble your parts. When you assemble everything you would be better off bedding your barreled action into that At-One stock which if you don't do yourself will set you back at least another $125 and that puts you to $935 +/- for your rifle.
That's why I've said you're better off buying one of the Chassis style rifles you linked earlier. At least the stocks on the ones you linked are more modular and you can change out a few parts to make them more custom fit to you. Right now the
ABA Howa 6.5 Creed is far cheaper than anything you can put together yourself, and connects a lot of things you seem to be looking for. It also retains the ability to upgrade butt stock, pistol grip, and forearm. Now you might want to thread it for a suppressor or brake, but you'll still have less in the rifle than if you start with the barreled action I linked you going the route you seem to be wanting. Plus you can sell off the parts you don't like to help recoup some money to buy the ones you do. That just isn't an option with the X-Ray 180 or At-One stock.
If you just wanted to put together a varmint/bench rifle by putting it in the Boyd's, bedding it, and putting your optics of choice on top then what I linked is still a good option. However, I don't really think that's the rifle you're going for. These are the reasons, I'm now trying to steer you away from the direction I originally sent you.