Since you registered on the forum to express this concern, I get the impression that this is probably an important issue to you, so let me try to assuage your fears a bit.
In regards to some sort of progression system like Paragon levels from D3, we are personally against such a mechanic as there is no end point to character growth, which we personally feel is not how ARPGs should work.
As for the power up mechanic, we did “put some thought into it”. In fact, we put a lot of thought into it and came away pleased with the result.
When progressing through the Shattered Realm, any character that relies on the Soul buff to progress is going to have a bad time because when (not if) it falls off, their character better be strong enough to withstand what’s being thrown at it. This is because the buff itself is actually very short duration (currently 18s), but you do get more stacks of it from defeating heroes/nemesis bosses. On top of that, any stacks fall off immediately when you progress to the next Chunk, and Souls do not drop on Boss Chunks, so you’ll need to be sufficiently prepared.
The power up is like a short burst of adrenaline where you get to feel like a juggernaut for a little while, and that’s pretty damn fun; it’s also fun to see how long you can keep it going, but I don’t think it’s going to be the deciding factor of how far a character can get.
I imagine once players have the Shattered Realm on farm status, they will know what a Shrine does at a glance based on its color/name, so no fumbling about necessary.
The lever room is not a puzzle, but what you do with the levers will certainly impact what’s ahead!