I've succeeded tying my armies to my economy after a lot of trial and error!!!! For those who hates how everyone gets like 1 million gold late in the game and nothing to spend it on:
GOVERNMENTS:
I started by giving 3 to 4 gold cost per unit per turn after you go over your unit support. I gave 10-20 free unit support depending on the government so that in the early stages it wouldnt be so brutal. I mean who could afford 3-4gold per turn per unit in the middle ages? I also played with the unit support per city. Basically earlier govs have a higher free unit support, but a lesser city support, that way you dont get in trouble unless you or the AI is trying to overdo themselves. All in all monarchy will still feel like monarchy in the early stages, republic will feel republic and so on.
Later govs get less free unit support while their city support increases, and eventually when u get to communism and fascism all free unit support is gone but city support and city support is left standard for communism and fascism. By this time support with your own gold is not an issue unless you are a warmongering fool who neglected their economy

. Oh yea and i added 4/4/4 support to democracy due to the cost for support being a little high.
ECONOMY:
I made gold more reliant on the resources and improvements than tiles themselves. I added collateral damage to some invisible units which will blow up your economy in a war. I gave +1 naval defense to economy buildings meaning that they will get blown up first when bombarded in coastal cities. The high cost per unit support was intended so that when the AI started to destroy your economy, you start losing decent gold per turn and use it as a form of war attrition for both humans and the AI. Unable to support ur troops you will be forced to lower research and you will start draining your coffers from gold every turn. Thats what i call a trade embargo instead of the puny civ 3 one, and its effects will be felt long after the war. You can do this also to punish economically the AI. Also air trade has been transferred to the commercial dock so that when you destroy all of them docks it can act as a forced trade embargo.
UNITS:
Last but not least. It looks ridiculous that the AI or anyone can just build a road to a resource, be broke as a bum, yet get the latest gadgets. My solution is to flag all the top end units of an age with the 'king' flag so they come off the build que and only available thru upgrade, and increase its cost to something doable within the age, but not so easy either. Even if you are a rich nation, if you are careless and you suffer casualties to your infrastructure, war attrition sets in and since every top end unit will need to be achieved thru an upgrade from its previous generation, in a not so distant future not only will u have a high cost to support your units, but you might also run out of gold to upgrade to the top end of the unit chain. Even if only suffer unit casualties you will need to build new ones and upgrade them all over again.
CONCLUSION:
I played it and im quite happy with how it feels. It stops being the simple minded civ 3 game which you just pump out units for 200 turns to try and control the world. There are other factors at play now, and if overlooked they could drag you back and take a while to make a full recovery. By that time the AI might have become as strong as you or even stronger.
NOTE:
This is a good thing to do for anyone who doesnt like to play the game on the highest difficulty meaning that the AI will cheat and all techs will be researched in about 100 turns. I like it at monarch and it feels more real and challenging for me. It is ideal for anyone wanting to enjoy each era, and enjoy trade and diplomacy instead of the good old warmongering ways

. I do not recommend modifying a mod for the highest difficulty lol. It might be overkill for a human. You will be killed twice.
Who knows maybe someone is wanting to make a mod with stuff like this but it never came to them. I hope this helps someone, and if u do make a mod with similar things I will also download. Im horrible at creating mods lol. I dont do civilopedia work.