Sid Meier's Civilization V

Sid Meier's Civilization V

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Add AI tech bonus per Era
I know this is a somewhat tired topic and I see a lot of similar threads about this over the internet (mostly older) but what I don't see are answers. These existing posts all seem to garner responses that either diverge from the primary topic or are simply left unanswered entirely.

My only interest is making the game longer and having the AI keep up technologically through the Era's. I do not want anything extra. For example, I'm not looking for a mod that might accomplish this but also adds a bunch of extra features. Again, I'm looking for a mostly Vanilla experience (I also own all expansions), just a longer game and an AI that can complete technologically. I know the AI is dumb, hence this topic.

I've been playing around with simple modding via two XML files; the Civ5HandicapInfos.xml and Civ5Speeds.xml. I feel comfortable modifying the various elements contained within these files but I'm at a loss when it comes to bonuses per Era. I'm aware of the "PerEraModifier" element represented as a negative number but as I understand it (and based on my personal testing), this does not apply to science. It would be great to have a similar parameter like this but for science.

Does anyone know how I might go about accomplishing this? Given how complex a lot of mods out there are, I figured someone has surely figured this functionality out by now.

Looking forward to your responses!