Hmm...
The rifle is disgustingly OP, I'm afraid. Stack it with the other abilities, and it's even grimmer. This is better than most relics. And it's starting kit. What's with that insane range? Sure: It makes sense in the real world, but not in the context of the game. We're talking about a game-world where gyrojet rifles only having a 100m effective range and support weapons only half that again!
The stat-ups: 2 cheap, no expensive. In-line with tactical and Apothecary, but basically a bit too good. why not use the 'some cheap, some average, some expensive' formula of most classes?
Talents/skills: There's a lot of them at each level, and they essentially build into an uber-sniper. Snipers are not Scouts. I also note the complete lack of scout skills available for early purchase, like tracking or awareness or similar. Lots of infiltrations skills but no actual scout skills... It kind of makes the ethos behind the class quite transparent: To build an uber-sniper. Tactics: Recon and Stealth is obviously not something that Scouts bother learning, because they're too busy murdering people from a million miles away with a rifle that makes Assassins hastily update their Xmas day lists.
The class skills are a bit OTT too. They basically make the class murderously good. If Scouts go on to become Marines, then why don't all marines have a 'save or die' kill-shot ability?
I'm not keen on Scouts in DW. Maybe a Scout Company sergeant, who is a veteran marine, but not just a humble scout, who isn't even a 'proper' marine yet. But that aside, this is a drastically OP take on the concept. If a homebrew class is drastically better than even the weakest of the published ones, there's a bit of a problem.
As regards there being a gap for a good Scout: That's part-true, but under-sells the Space Wolves as regard pointman duties. SWs are great for the role.
There's been a lot of talk about how the Space Wolves are a poor Chapter choice. How about GMs simply houserule a few more basic 'outdoorsy' skills and talents onto their list, and the search for a suitable 'scout' is then over?