One of the biggest problems I see is that "Westernizing" isn't looked at as it literally is worded. Historically, as everyone is very quick to point out, Western Europe was not at the forefront of the world in technological advancement or even government and organization, until well after game start. In 1444 they should be behind, and not until the 17th century should they pull ahead... in the general concept of technology.
Technology in the game is hardly just raw knowledge. It's application. The idea of "westernizing" in a historical sense had two different meanings; one was the stereotypical Peter the Great taxing beards and trying to shift culture. The other is easy to see all over the nerfed horde complaints where they cite example after example after example of these ROTW people using "western" military tactics. The former, changing some non-western country to function like a western one, is certainly something we'd all think should be very rare and very difficult. The latter, which is just adopting the advances in use and application for technology that this thread has beaten to death the point that most of the world already had, and changing strategies to what Europe was doing (without changing to western culture or government) is an entirely different westernizing. Calling it westernizing/westernization is hardly racist; that's EXACTLY what is going on.
The problem here is that everything was rolled into one, a tech group. If they separated out technological advancement and innovations, similar to how ideas are split off, that could perhaps address it - you would need to have tech researched as one purchase, and then the advantages of it (tactics, CW, unit upgrades, etc) unlocked separately, allowing indian/Asian countries to closer-to-realistically keep up with tech just fine, but have a difficult time applying it. Westernizing would likewise need two functions - one to pull a Russia and adopt the whole culture and feel of Europe, and one to pull a most-of-the-east and just adopt Western firearm use and the like. The former should overhaul you to western and be a nightmare to do, but the latter should be simpler and just give you western unit groups.
The point though is to realize that so long as everything - technology, innovation, application, and traditions - are all spun into a single category called technology, it's going to be thoroughly impossible to make it perfect when you have countries that are current (even ahead) in some parts and way behind on others.