I've had quite the time with this frame really, I was following up on it since Liger's fan concept art. And I wasn't dissapointed when I got to know his abilities and I'm still having a lot of fun with them. However, I had my doubts about the exalted Shadow form. I still do. The bright side:
The frame's design is perfect for someone that loves survival missions.
Reap: A very good damage + debuff ability. Even if it doesn't kill enemies by itself, we can combine it with Sow, which feels very good as a design choice to make players use all the potential a frame can have. The debuff that it inflicts enemies with makes this ability even more useful than other first abilities.
Sow: The combo with Reap is what makes this ability really really good. The radial damage bursting out from enemies can make this a deadly ability in overwhelming situations. And even if enemies stay alive, the dot effect combined with Reap's debuff could potentially finish the job with some viral or corrosive stats or with the player helping out with some gunfire.
Gloom: Now this is something new, something refreshing. Dream ability for all survival and higher level missions. The life steal is perfect, the constant slow makes sure that no matter how many enemies are around, there won't be enough time for them to kill Sevagoth if he steals life from something constantly.
Exalted Shadow: A tanky and strong form of the frame, having it's own cc, lifesteal and debuff ability it can use. There's ALMOST nothing wrong with it.
Sow, which is another ability that inflitcs some effects on enemies for a certain duration. And yet it is another ability that is not recastable before the duration on every single enemy expires. This is just a minor problem with the kit, but it's still annoying. It either needs to be recastable with duration refreshing or with some other mechanic. Gloom, dream ability for every high level survival mission. But the energy cost... well let's just say that streamline alone will not suffice in any situation to keep up with the energy consumption rate. Now after 30.0.6 hotfix, it got even worse. The previously fixed, and with some mods managable, energy cost became dependent on how much enemies are in range. Now this isn't a problem when there are no enemies around, you can freely carry the effect to other rooms, but when enemies are constantly coming in, like in survival, interception or defense, the energy consumption kicks up to the sky, and it will stay up there, because enemies won't magically stop spawning, only between waves.
I highly suggest reviewing the math and values behind this ability, because it's just insanely energy hungry. The biggest problem with the frame however is with his fourth ability, the exalted Shadow form. Now don't get me wrong, the Shadow IS amazing. It's tanky, has high range crowd control, lifesteal and can even debuff enemies. The problem with it is the ridiculously low effort a player needs to make in order to cast the ability and remain in the Shadow form. Once someone has a decent build, the difference between the time spent in the Shadow and the time spent in the frame itself becomes very noticable. We only need to cast Reap and Sow like 2 times and we already maxed out the Deathwell and we can go and don't give a damn about anything but the Shadow and it's exalted melee claws. The frame has such a good design and with little tweaks all his abilities could make the finest kit together in the game for a frame that's all about sustain and aoe damage. The Shadow form takes this all away.
The effort we need to make needs to be increased, because this just makes Reap and Sow almost entirely forgetable.
Better idea: Add a mechanic that could allow us to release the Shadow just like Wukong's clone. The Shadow would be able to use it's abilities and Sevagoth could fight alongside it, commanding it with Reap when it's free. This could make the frame and the kit even more interesting and would fix the problem mentioned about this ability above.