Again, you are trying to push your personal preferences as general rules, imposing your preferable model of gameplay on others.
Ditto for you, only you do it in reactionary way.
There is also a limit to this: only 4 trade routes per city available. This should be enough limitation.
Thats way too many, with numbers of cities people have it means over game you end up building sick numbers of caravans.
If some people prefer this kind of play, why prevent them from doing it? It adds to variety and increases the number of choices you can make through the game.
For at least third time: theoretical options do not translate to practical options. Trade routes are not optional, they are a must as they are currently so there is no variety and no options, you have to build that shit.
Why should there be any pressure to expand? Why shouldn't people have more options available instead just one: conquer, conquer, conquer? There are many historical examples where this was a perfect winning strategy.
If you read carefully my suggestion does not remove that option. It removes magical defense cheesy crap though. Wanna trade? Ok, I support such choices, but getting huge free bonuses (aka no way to eliminate trade routes) is just bullshit.
apples and oranges. I can't speak about mmo stuff as I don't play them, and in general view them with derision. But strategy games are different. Maybe you heard of a game, was decently popular RTS, the company that made it kept tuning and balancing for like dunnno 10 years, many people agree that thats the reason why that game stayed (and still remains) active and with serious pro community while tons of games went through many iterations while not going anywhere. Starcraft it was called, might have heard of it.
Yeah I get that I complain about a lot of things. But thats because I want game to be better. But game balance is quite a real thing and strongly dominant strategies, even if you like them, do not make game better. And currently trade routes are very strongly dominant. Dem and Repub are also insanely dominant on default ruleset, a bit less so on civ2civ3. That does not really add anything to game, everyone is forced to take same path. Then everyone is limited in diplomacy department.
As for expansion, well basically all games, computer or board, are about expansion of influence, and its mainly done by territory, just like in real life (and not only applicable in war). There are some unique peculiar board games that might work in very different and weird games, and they are quite ok in fact (zertz is a nice example). But strategy games are mostly about territory logistics and diplomacy. Currently however there are many ways that push back territory game, push back not as into back seat, no push back as in time. Territory war has to come and does come, only later. But there is absolutely no point in that. Sitting on camels while going to spaceships looses ton of time and ton of game with it as ton of stuff is seriously underutilized, talk about loss of options...