Pardon my ignorance, but why would 4TPY mess with the economy? I thought it just 'stretches' time as far as everything else is concerned, if indeed building costs/times are not tweaked in any way. At least my Roman campaign seems to be going as usual, for now. Of course everything will be moving a lot faster e.g. what my date used to be ~630AUC it's now ~580AUC. I never bothered with the year since it's all an alternative simulation to historical reality, so it doesn't bug me much.
Anyway, what I meant to say is that playing Rome I've had income of ~115K before I applied 4tpy (which is not much at all when investing in buildings in a huge empire). I ran the submod and after several turns and no real change in my troops/income composition, I still have around the same income. Maybe being filthy rich is normal for Rome so I can't really tell the difference? I have to try out my Gallaeci campaign but I've ignored that save because it's H/H and Rome and Carthage have got me between the hammer and the anvil if you know what I mean