I am a complete doofus when it comes to IT and am probably posting this in the wrong place, but I too am keen to mod the original game and have looked into Stainless Steel (I think 6.4 is the most up to date version) but I have one or two reservations:

My favourite factions are:

Byzantium, because of their horse archers but it looks like their units of this type have been severely weakened and you cannot get varditori until much later in the game.

England because of their archers, but now loads of factions seem to have stake laying, amour piercing units.

Scotland because they had to rely on a few special units, but now they get Scots Guard (which I know makes some sense) and their border horse look rubbish whereas they use to be very good light cavalry.

Is my research just rubbish, or will Stainless Steel, for all its improvements, lessen MY enjoyment of the game. If so is there another mod that would suit (The Longest Road for example)