A few people mentioned these buildings are too good so I'm trying to calculate them.
For the baseline, we'll compare LT to Wizard's Guild and Monument to Magic Market
Wizard's Guild : Cost 600, Upkeep 5, Produces 13 magic resources per turn.
Linking Tower : Cost 400, Upkeep 5, Produces 1500 magic resources once on completion basically.
Gold upkeep can be converted to magic resource production via alchemy, so 5 upkeep is worth 2.5 less resource production.
Wizard's Guild is more expensive so we want to convert it into an amount of resources for 400 production investment, so we have to multiply by 2/3.
This means Wizard's Guild produces (0+7*Turns) total magicial resources for each 400 production invested.
Linking Tower produces 1500-2.5*Turns for each 400 production instead.
It's easy to see that Wizard's Guild becomes better over time, while Linking Tower becomes worse, as intended. The question is, how many turns does it take for the two to break even?
1500-2.5*T = 7*T
1500 = 9.5*T
T= 157 Turns
However, there is a fatal flaw in this calculation, and that is, Linking Towers only generate combat SP, not overland SP.
Assuming combat SP is worth half as much as overland SP - you basically have to also build Amplifying Towers and pay their maintenance to make up for the missing overland SP,then we get 750 = 9.5*T, T= 78 turns.
What this means is, if your strategy greatly benefits from combat casting and doesn't need overland casting at all, then Linking Towers are more economic for you if you decide the game in your favor within 157 turns which is extremely generous.
In a more realistic case of requiring combat and overland skill equally, the Linking Tower will still be more valuable for you than the Wizard's Guild for the first 78 turns which is typically enough to win like two wars.
Needless to say the combat spells also earn you extra resources by winning battles, so the Linking Tower can give you an immediate benefit over the Wizard's Guild that is hard to quantify but you also need to invest mana to use any combat skill, so it's not strictly a resource by itself. If you don't actually use the extra skill, or not in a way that decides major battles in your favor within those 78 turns, the building does become an inferior choice. If you do however, it might be the difference of losing or not losing an entire city. I do feel that 78 turns is a bit too generous for this benefit.
Magic Market : Cost 72, upkeep 2, produces 6 magic resource/turn
Monument : Cost 72, upkeep 1, produces 150 SP.
150-0.5*T = 5*T
150 = 5.5*T
T=27, considering it's combat skill only, T=13
Much worse investment here, you actually need to fight a decisive battle that uses the extra skill within 13 turns of completing your Monument, otherwise your Magic Market would likely be better.
Of course, in the early game, the extra skill added has more snowballing potential and is of higher relevance as it basically unlocks using spells or strategies compared to the Linking Towers' "Yes, I can now cast a fourth Doom Bolt or third Flame strike per battle", so we do want this number to be much lower than Linking Tower's, but it's still probably too much.
Overall conclusion :
Maybe Monuments should produce 180 SP and Linking Towers only 1200? Maybe Linking Towers could go back to having a higher maintenance? For example 7?
For the baseline, we'll compare LT to Wizard's Guild and Monument to Magic Market
Wizard's Guild : Cost 600, Upkeep 5, Produces 13 magic resources per turn.
Linking Tower : Cost 400, Upkeep 5, Produces 1500 magic resources once on completion basically.
Gold upkeep can be converted to magic resource production via alchemy, so 5 upkeep is worth 2.5 less resource production.
Wizard's Guild is more expensive so we want to convert it into an amount of resources for 400 production investment, so we have to multiply by 2/3.
This means Wizard's Guild produces (0+7*Turns) total magicial resources for each 400 production invested.
Linking Tower produces 1500-2.5*Turns for each 400 production instead.
It's easy to see that Wizard's Guild becomes better over time, while Linking Tower becomes worse, as intended. The question is, how many turns does it take for the two to break even?
1500-2.5*T = 7*T
1500 = 9.5*T
T= 157 Turns
However, there is a fatal flaw in this calculation, and that is, Linking Towers only generate combat SP, not overland SP.
Assuming combat SP is worth half as much as overland SP - you basically have to also build Amplifying Towers and pay their maintenance to make up for the missing overland SP,then we get 750 = 9.5*T, T= 78 turns.
What this means is, if your strategy greatly benefits from combat casting and doesn't need overland casting at all, then Linking Towers are more economic for you if you decide the game in your favor within 157 turns which is extremely generous.
In a more realistic case of requiring combat and overland skill equally, the Linking Tower will still be more valuable for you than the Wizard's Guild for the first 78 turns which is typically enough to win like two wars.
Needless to say the combat spells also earn you extra resources by winning battles, so the Linking Tower can give you an immediate benefit over the Wizard's Guild that is hard to quantify but you also need to invest mana to use any combat skill, so it's not strictly a resource by itself. If you don't actually use the extra skill, or not in a way that decides major battles in your favor within those 78 turns, the building does become an inferior choice. If you do however, it might be the difference of losing or not losing an entire city. I do feel that 78 turns is a bit too generous for this benefit.
Magic Market : Cost 72, upkeep 2, produces 6 magic resource/turn
Monument : Cost 72, upkeep 1, produces 150 SP.
150-0.5*T = 5*T
150 = 5.5*T
T=27, considering it's combat skill only, T=13
Much worse investment here, you actually need to fight a decisive battle that uses the extra skill within 13 turns of completing your Monument, otherwise your Magic Market would likely be better.
Of course, in the early game, the extra skill added has more snowballing potential and is of higher relevance as it basically unlocks using spells or strategies compared to the Linking Towers' "Yes, I can now cast a fourth Doom Bolt or third Flame strike per battle", so we do want this number to be much lower than Linking Tower's, but it's still probably too much.
Overall conclusion :
Maybe Monuments should produce 180 SP and Linking Towers only 1200? Maybe Linking Towers could go back to having a higher maintenance? For example 7?
