I do agree with some of your points, and i'm sure you'd find a lot of support here for your issues.

Unfortunately, CA has chosen to aim for a mass market appeal and make some historical omissions that will be picked up by people such as yourself.

Balance is definitely an issue - the entire game model would have to be redesigned for ships and armies to be able to move an accurate distance each turn, and that was never going to happen on the rtw engine, unfortunately. Hopefully some progress will be made on that front with the next game.

And i do suggest that you check the unit roster for the english - i'm almost 100% sure that they can build arquebusiers at the top level barraks in a city after gunpowder has been discovered - I can't check atm, but have recollections of doing so in my english campaign.