15% crit on evisc is 3-5% DPS depending on what other traits you have. It's as strong as the nightblade and shadowstrike talents.
Anyway, I was obviously curious as well, so I graphed out various paths I could think of.
Here are the results.
The bottom graph is more representative of DPS over the course of time, as it is scaled based on total AP spent. I capped it at 25 traits spent because by that point the amount of power you spend gets pretty extreme, and all you can see is the last couple points you spent.
Notes: The bottom path is way more competitive than I expected (Path D and E) since you get a lot of damage early, and then evens out with the others later. But as you pointed out, early damage is important both for progression and because artifact power costs scale exponentially.
In practice you'd end up getting a long droughts when you need to fill out the dodge talents and they cost tens of thousands each which could get boring, but you may want to spend that time leveling up offset weapons anyway.
Gutripper first and then bottom path (Path E) spikes up later than Path D because it gets the golds later, but it's above Path D for a good part of the curve as you can see from the bottom graph.
Top path to akaari's before finality (Path C) I shouldn't have even bothered graphing, because finality and the traits leading up to it are better than akaari's, and after you get both it's the same as Path B.
My original suggestion of Path A (top path down to finality + nightblade + shadowstrike, then akaari's and shadow nova) provides a reasonable curve, but ends up being worse than other options at almost every point.
I'm realizing now I should also try bottom path to finality, then gutripper, then akaari's soul and shadow nova (or just give up after gutripper)
Added as Path G: Follows the same path as Path E but spikes earlier, since it gets finality earlier, then stays ahead until around 20 artifact points and then spikes ahead again once it picks up Akaari's. (Which, granted, isn't until 26 with this build.)