There’s many ways to go about that IMO. I could easily see them making something based on the dark rangers. However, this is something I went into detail a few weeks ago for fun, so I’ll just link that thread here. It has themes I’d enjoy, base spec and how it might function, and talents. Obviously I don’t expect blizz to ever do an idea copied like that and I’m not exactly sure how balanced all of the ideas would or wouldn’t be.
https://us.forums.blizzard.com/en/wow/t/4th-spec-rsv-munitions-expert/871855
Feel free to read through and comment though with thoughts or feedback ^^