Look at upgrade costs in Faeries Era. T2 manufactories population costs are enormous. Elves Silk upgrade from 15 to 16 require 919 pop. If you have 3-4, multiply this accordingly. I have 4 of them, and 60 Residences 17lvl. Their upgrade can give me 4800 population at cost 2280 Culture, 41.100.000 Coins, 2.364.000 Tools, 51.000 Steel, 61.200 Scrolls, 75.000 Crystals and 34.000 Elixir. Many? Now you imagine this is enough to max out only 2 and from 15 to 16 in 3rd Silk Manufactories... Costs are enormous and probably many people will be forced to resign from already maxed (15lvl) one or more Silk manufactories, to handle this. I don't even mention costs of Residences upgrades. Owners probably were jumping to empty pool on head... Many times
They don't changed size but building time increased twice (from 5h to almost 10h), Coins seven times (!) from 53k to 370k, Tools from 7k to 23k... and other Goods I don't mention, because it is not worth. And all the costs changed income from 1769/h to 1859/h. To compare, when Dwarven were introduced, Residences become one square smaller and them gets twice as much bigger income (180/h) from 1500/h to 1680/h
Only population gain was smaller... Not 40 (Faeries) but only 20 (Dwarves). But hey... Buildings became smaller, so logically population shouldn't even increase
All this points to simple conclusions:
- players should have as many obstacles as possible to upgrade buildings,
- there are bigger chances that they buy diamonds to make something easier,
- enormous costs are to drain players from coins and tools,
- repeatable quests will be even more overused, but I suspect owners change them too and them became much less profitable,
- Faeries and later races AW will be more and more overpowered (Dwarven Mountain Halls aren't as shitty as Elvish AW), but getting runes for them will by real pain between the butts
Again Diamonds will solve problem...
Of course there is more conclusions, but biggest from them is quite obvious: "You don't pay? You don't play!" More and more advanced you are, it will be more and more visible. You may play without money maybe to end of 4-5 era. Later at least 1 extra worker is greatly welcomed. Then extra expansions. At some point you realize that playing without diamonds is taking a lot of time and looking at ranking is making you angry, because even players that are 1-2 era behind you (!) are having more ranking points than you. Only difference is that they pay for game more than you. Rather not very optimistic view. And game started to look that way already. Bitter words, but look around you and try to say "That is not truth!". You probably cannot, because will find that kind of players.