About max shields, assuming I'm playing a game in which there is a battle brewing in the late stages, I try and shoot for at least one city (coastal) that can produce 102 or 104 shields. With a port facility, I like to crank out massive numbers of AEGIS Cruisers.
Since I almost always wage even massive wars in Democracy (personal choice, because IMHO, fundy/commie is too easy)... trade is an issue, meaning you shouldn't just make lots of forests to crank up the shields. The lowly deserts are awesome for shield production in a democracy... you can get the shields and food of a forest (post-refrigeration), and all the trade of grassland/plains.
IMHO, such specialized huge shield-output cities simply don't need any pollution control devices until Solar Plant. It's OK to have them, but a waste, really. That's because the city is gunna pollute no matter what you do when the shields are in the 110-120 range, until a Solar Plant comes along. I simply assign a full time team of 2 engineers, and write off their 4 food and 2 shields of support per turn as a fixed cost for producing a new AEGIS cruiser every turn.
You can usually follow the long line of ships right back to the source city after several years, because it seems such cities are almost always located several turns of movement from the front where the ship is needed.
On some occasions, like a random game I played last month, you can't quite reach 100 shields per turn (for the AEGIS) in a city you'd like. In that case, cycle older units into the city and disband them (especially captured junk that won't be upgraded because you're post-Automobile & no Leonardos)... in effect, they become AEGIS cruisers. In this case, the 90 plus anything equalled an AEGIS every turn, and the AEGIS then ducked into another nearby city to change ownership.
In GOTM 5, I had several 80+ cities. One city was 96 shields per turn... without a mfg plant! But since it was landlocked and the game was long since under control, there was no real point in maxing out the production with a mfg plant. That city was a "120", albeit incomplete. Had I converted a mountain to a hill-mine, it would have been a 102/128 city. It was not finished growing at the end of the game, but would have reached size 37 (using airfields on hills, or 27 without them).
EDIT: Typos
[This message has been edited by starlifter (edited June 28, 2001).]
