I highly value the charge stat and the charge:maneuver ratio, but I do see what you mean when focusing on certain horses' advantages. The 6 difficulty horses (minus courser) are decent at everything, while the higher difficulty horses satisfy more specialized needs. Which horses work better in a direct clash or when making best use of their strengths can be difficult to determine. I personally believe that some difficulties could be lower after looking at it again.
I was unsure how the changes to the top 3 would work out. I still think the heaviest horses should be cheaper, closing the gap between the large warhorse and cataphract a bit more, and cheapen plated charger by another 5k. Using the large warhorse, it feels like it's in a good place price-wise, making money when performing decently. I have a +3 charger that I switch to with a x3 or better to break even, and often times see the gold jump up and down pretty rapidly. It's really fun to play and kill archers with the charge damage, though.
Other than that, it's pretty difficult to have a conversation about the stats when no one really points out what set of stats would work better. Before, we had jumps like 24->34 charge from the padded warhorse to the warhorse, and 47->60 armor for the eastern warhorse to the charger.