Granted it's only anecdotal evidence, but with helping my dad do his Tournaments, and also occasionally when he askes my opinion on Spire fights, I've been noticing with his just beginning Ch.18 cities:
a) His troop production, despite having a Lv9-11+ Simia is NOT keeping up with the Training Ground/Merc Camp losses. The only reason his Barracks troops totals stay consistent, (rather than growing per say), is due to AW's like Bulwark, Temple of Toads, etc...
b) His cities are more and more dependent on boost buildings + Fire Phoenix to even fight.
Luckily he's been able to generally recoup the 3 crafting buildings per week in each city, and often times can pick up 2-3 extras as well. But it's very RNG reliant and all it will take is a couple poor weeks in a row and he'll soon run out of boost buildings.
c) In a couple of his cities, Dwarven Armorers have basically dried right right up. While I can help him maintain about 2.4-2.6k tourny pts per week, trying to burst through beyond that is basically impossible unless he drastically re-engineers his entire city to hyper focus on troop production by adding in 4-5 more armories.
d) If he gets too many 'auto-lose' fights in the Spire, especially on the 3rd floor, it basically eats up 1-2 weeks worth of goods production.
Again, too much RNG-screwing in a single week can set him back a month or more in terms of resources for researching/upgrading city buildings... this is absolutely asinine and a symptom of a completed broken system!
Now, if he didn't already have a substantial stock of boost buildings from when they came up more often during earlier events/quest lines, etc..., AND, if he wasn't so seemingly RNG-blessed in his crafting, my dad's Ch.18 cities would NOT be able to maintain Lv.3 Spire + Tournament play on a weekly basis.
The numbers are just too large, and the fact that the devs allow for impossible fights to happen is an absolute insult to basic human intelligence which further screws over the players.
THE. FORMULA. NEEDS. TO. BE. REWORKED!!!