As of this writing, I'm hunting my 5th Kuva Lich. I'm pretty familiar with the game-play at this point and wanted to offer some feedback for consideration. Overall, I'm really enjoying the update and I think the Kuva Liches are a good addition to the game. Having said that, I think there is some opportunity to make some of the game-play loop more rewarding and a little less demanding of our time.
The dynamic appearance, voice, and attributes are awesome. I was shocked to see the Tennogen helmets were also available as Lich adornments, bravo!
Scaling difficulty is interesting. I welcome the tension and sense of urgency as the Liches grow stronger and exert more influence over the Sol system.
Absent markers and their health bar on top of the screen, the Liches don't necessarily stand out among the crowd in mission. If they were a bit bigger, had flashier colors, or perhaps a bright aura about them they might stand out a bit more from regular Grineer troops.
It would be nice for more of the game to react to the presence of Kuva Liches. For example, have Lich-specific dialogue on the scanner or from Nora. Perhaps our operators could infrequently say something in response to Lich banter. Outside our orbiter window, if there were Grineer ships bearing the Lich flag w/ matching colors, that would be cool.
Most enemies have limited mobility in stark contrast to Warfames. I think Lich engagements would be a bit more engaging if they featured dramatically enhanced mobility and and some sense of self preservation. As it stands now, they pretty much just stand there while you shoot them in the face. I vaguely recall watching a GDC video from one of the Digital Extemes developers talking about how you used data from players to instruct how specters traverse mission terrain. Perhaps there is opportunity to leverage a similar approach to instruct Lich behavior and mobility.
Sphere of Influence Missions & Thralls
Seeking out Thalls in mission is fun and engaging.
As a tenured player with tons of materials, credits, mods, endo, etc. the end of mission taxes are inconsequential. I think this is compounded by the relatively low percentages that are at risk. Similarly, when you finish off the Lich and you're rewarded with all your missing bounty it's underwhelming. Ultimately, I think this aspect of the loop could use some tweaking.
It would be nice to have a thrall-specific drop table with interesting rewards. Some rewards that I think would be relevant to the Lich game-play loop are void traces or kuva. These too would be subject to the end of mission tax.
It would be nice for the Grineer enemies on Lich controlled missions to take on the thematic appearance of your Thrall - color scheme, energy color, etc. Similarly, in mission have some Lich graffiti on the walls/floors or banners in mission to drive home the immersion of their presence.
Establish opportunities to earn requiem relics in Lich mission nodes - sprinkle them in spy, sabotage cache, excavation, end of mission reward tables. Every once in a while getting one of those relics while running the missions would be a nice feels good moment.
If the thralls were an incremental threat, that would be welcome too. Consider re-purposing some of the units from Rathuum and crank their levels up a bit from their peers in mission. This would give us a different silhouette and a little more challenge making each Thrall engagement a little bit more rewarding.
Requiem Relics & Mods
There's whole separate loop for getting the relics and running them separate from the rest of the Lich system, any opportunity to integrate these loops a bit more would be welcome. Ideas offered above about getting relics or traces in Lich controlled missions or from Thralls would be one way to connect the loops. Similarly, you could have thralls spawn into the Siphon or Requiem Relic missions to help connect the systems - this way you're still making progress (or have an opportunity to make progress) regardless of which loop you're actively working in.
I've only seen Rescue and Survival for the Requiem relic missions - I'm not sure if that's just my firsthand experience or by design constrained to these 2 mission types. If it's the latter, I'd recommend opening it up to all of the Kuva Fortress missions.