I just wanted to put these here. If you want me to mantis any of them I of course can, but I didn't want to spam it by dumping lots of them there, and suggestions fit the forum better anyway.
Issues and suggestions:
AI (And possibly minor factions) should kill the Devourer golem if they have enough forces- in my first fallen spire game it sat snacking on the homeworld defenders of the 1st AI for most of the game including killing all the dragons, since the praetorian guard just sit on top of it, and if it gets trapped on the far side it'll just never leave. This eventually happened in the second game as well - though it took longer to cause it, it still occurred naturally. Even if this is not done, the AI certainly shouldn’t be deploying the praetorian fleet against the golem and just sitting it to be eaten.
AI Overlord phase 1 is a mk0 unit? (Matters for fleet XP)
Suggestion: Using science to level a planet should give increased Mk level to irreplacables, increasing their health slightly. This just seems like a nice extra- I think the existing costs are high enough for this to not be overpowered.
Spire Balancing:
City Structures:
The Buttress:
It’s far too weak for its cost at the moment. It's a nice effect, but consider that its health is barely above that of a single Mk5 forcefield. While it has added utility for defending against forcefield bypass ships, consider that the Great shield defends everything else as well, has ten times the health, also defends against forcefield bypass for longer than the buttress will by dint of its sheer radius, and takes only 3 sockets including its power generation.
When compared to science for command station upgrades the buttress also seems to come off badly: The first 1000 science gives a mere 50k actual health to a mil command, true, but the forcefield health increase from upgrading a set of four FF's to MkVI is almost 800k, and the science upgrade also helps cover any turret level deficiencies – and in FS, science is cheap – even a second upgrade for a total of 4000 science is nothing for a chokepoint, which is more than 700k more forcefield HP and another 50k health, not to mention a hefty increase in firepower.
I feel that a unit costing 6 spire city slots (4 for itself, plus the energy requirements, and being generous by ignoring the engineering station since if you want a buttress you’ve probably already eaten that slot cost to put a fortress up.) really should outperform a single MkV forcefield in more than one specialist task, or should do that specialist task much better than it now does.
(My suggestion would be to either: Remove its energy requirements, triple its health and shields, reduce it to one slot and allow it to affect the home command station, or keep current slot and energy requirements, keep the home command exclusion, but make it affected by city level and have its health and shields equal to a lesser spire fortress of the same Mk.)
Other stuff:
It seems odd that the lesser spire fortress has sniper range on its energy wave, but the greater spire fortress has a large but finite range.
I’m a little puzzled why the Shard Reactors and the Great shield don’t level up. The other structures are either high level only, or have another scaling benefit, like the level of the ship they provide increasing, or have a strong specialist benefit that transcends mark, but 1million energy is not a lot in late fallen spire, so it would be nice if the shard reactors had scaling HP and damage. Meanwhile, the great shield could be slightly lower HP and/or radius at lower marks, current health stats and full radius at MkV or so, and maybe up to 20 mill shield HP at MkVII?
When the AI retrieves relics from trains, the ships it gets should probably advance in mark as things go on. Getting a single Mk1 spire battleship feels rather too friendly to the player when things are at 1866AIP, with dozens of cities, every exo strike contains dozens of units with far more strength than the battleship, even accounting for the way spire ships have too low a strength, and the threatfleet is sometimes being given motherships, even on a FS plot intensity and AI difficulty of only 7 each.
Since the Nanocaust cannot be "Defeated" officially, should the requirement for it to retrieve debris be that it owns a planet? Otherwise it just lets you avoid the consequences of losing debris.