Everything up until the first portal reset felt pretty solid, second loop was faster kind of but the combat feature unlocked helped get through the waiting. Decent experience for a couple days doing a couple loops.

(Really need an upgrade that let's us toggle multiple relics with the Phylactery because constantly swapping it around is painful)

After that it gets super slow, you don't get enough essence per loop to really push anything (most time per loop is just spent making buildings) and the soul perks from combat while a couple are useful during reset (essence research and keep training levels specifically) nothing else really impacts the rest of the game for the vortex essence grind.

If the essence ramped up more than it does it'd feel better but unless you want to sink multiple days into loops I currently get 80-120 depending on how long I'm letting it go. If research and construction times were getting much faster I'd not be too bothered but even with levels and research and the relic thing it still takes like multiple hours to full days for some building upgrades and the essence gain from it doesn't feel great. But even "fast" runs take a decent chunk of time and don't give almost any essence. Along with there currently being no automation for any of the construction stuff so it currently needs to be constantly managed for progress.

Then the current combat system. The random modifiers on gear feel really bad since it's pure rng if you get any modifier that might help speed stuff up along with a lot of low values there. Kind of to the point that outside getting enough souls for a couple soul perks to be toggled combat doesn't currently feel worth engaging in much past that (given it's WiP and getting expanded on) and I don't think the rng stats on gear should have modifiers that affect the other stuff outside combat but rather have some other soul sink that effects the other stuff, needing to try and get gear sets to boost specific stuff and swapping between them per loop for different boosts isn't enjoyable.

All in all it's a solid base for the game and I can see it getting really good in a couple updates just currently have a couple gripes maybe due to it being wip. I do hope development goes well.