So I've played a few games where I play hyper aggressive in the Modern Era (Immortal) and I started just assigning conquered settlements to Hubs (this is easy to do early, but that's another issue). This yielded hilarious amounts of diplomatic influence despite my war mongering with some settlements generating 40+ influence per turn, but usually I see around 10 influence per turn. My highest so far is 65 influence per turn, screenshots attached. Needless to say this defeats the purpose of having penalties for taking over settlements and really doesn't make a whole lot of sense, especially if you're still actively at war, to make these occupied settlements hubs. This feedback also helps you generate even more influence to use to garner further support. I guess the world just wants me to topple everyone when I can pay for 900+ influence costs in a few turns. One of the games, I managed to get a civ to -25 war support, but with some fairness I was prolonging a war with the last civ isolated on a nuked island to get all the legacy path XP... Either way, I don't feel like I should be getting enough influence to enable this with warmonger habits.
One suggestion would be to not allow occupied towns the hub town assignment. It digs at the heart of the issue, which is getting influence through world domination. Alternatively, if the feature of occupied towns being able to take on Hub focus is intended, I would suggest either limiting the amount of Hub Towns you can have, whether by a hard number limit or one per a set radius. Either way, I believe that there needs to be some change to this mechanic because it's pretty ridiculous generating 500+ influence per turn as a warmonger.
Thank you for taking the time to read my suggestion, and I hope this feedback is taken into consideration to better balance the game, especially in the Modern Era. I really enjoy this game and I look forward to all the improvements being made through patches.