TLDR;
The community and retaining player base is the driving factor of monetization and game interest. Instead of trying to make money from a spark of life (which they can just restart the mission). Build a fun game with a community, make players feel like they can help others and receive help from others. In turn, this will start the fly wheel for everything again.
We are seeing an influx of returning players. This game has its characters that have allowed it to flourish and be one of the most popular games on the planet at one point, and I think its still got the bones and muscles to do so with a couple minor tweaks.
1. Revive your teammate with half your health, when you have 1 bar, you can even give your friend half a bar.
This was one of the most heart felt features that I feel like this game had to begin with. This is how players bond with each other and introduce social interactions that continuously drive this game forward. Increased player base, player bond, and community.
2. Mist/Energy for elevators (Make it feel like doing the dungeons is an investment.)
There needs to be pain for there to be gain. This incentivizes players who are less experienced to find players who are more experienced to ensure completion of their investment, back to the community portion.
3. Rethink the forge crystals heating logic. (I feel like this was a tedious feature)
Anyway, these are all thoughts, I'm sure it can be done better. Throw your ideas down below --- and devs/managers, let's think long term.
I, and most people I know, do miss reviving teammates.
Nobody I know misses elevator energy costs and mist energy by association. Hearing that as a suggestion to return makes me genuinely believe you are acting in bad faith. It is genuinely, the worst suggestion I have ever heard of.
Forging is whatever, a bit too grindy, a bit silly, makes heat feel kinda meaningless, and in particular rads are too grindy to amass, there's a bunch of ways that that could be alleviated though to make it not feel annoying. Like making forging possibly at any floor, or automated, and making rads appear in all of S6 instead of just half, or making more varied options to farm them, like moving danger missions to the latter half of S6.