I;ve been in my Guild for nearly 3 years While the core of the Guild has stayed the same, we've had scores of players drift in abd out. Also I;ve sold Traz Goods to Guildies since Jab 2016. My observations are:
many players will only build the smaller goods buildings
Every new player falls into this trap. Some never climb out. I suspect this is the single biggest factor in the scarcity of various Goods.
Remember Ardak? He used to spam Fertilizer Plants because he knew he could always trade it away. My startup had Stone and Limestone. Never bothered with the others, necause they are always in demand.
because more of it is used in that GB.
This is the second biggest factor in Goods scarcity. I've been in CE for half a year. CE players have access to three Goods sources and still Robots and Electromagnets (needed for Inno Tower) are always in short supply. I produce both, Hoodies snap up trades offering either within the day.
As a long time Traz salesman it's all about Machine Parts, Explosives, and Gasoline. I was lucky enough to produce MP and Exp while in Prog, and never had any problems trafing for the other three. 41 Traz sold (Only a dozen Chateaus, bit that's another topic,), so i've collected a lot of earlier Era Goods. Which supports the first point, I've got a lot more Paper then anything else.
Through PME the Goods needed for Tech are balanced, but that's across 4 Eras. I haven't taken a real close look at the needs per Era though.
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I don't see a need for being able to switch Goods Deposits. A reasonably mature ciry of any Era has multiple ways to produce Goods, such as GBs, Special Buildings, farming RQs, and trading.
My LMA city is still on the HMA Continental Ma and I have not unlocked 4 of the Goods production on the Tech tree. No Goods buildings, don;t need 'em. I average 80 LMA Goods per day due to 3 Goods GBs, 3 WWs, random GE ptizes, and farming a dozen RQs per day. Since those payouts are all random, I have a balanced inventory of all LMA Goods
I see this Proposal as the author needing to learn the game, not INNO needing to change the game.