If at all possible, I will potentially try to make a new civ featuring the Crusader kingdom of the Knights Templar. If not the Templars I might go with Hospitallers or another crusader faction. Essentially, this civ would be an amalgamation of the Britons, the Teutons and the Byzantines, the three most represented kingdoms of which mainly composed the soldiers leading the crusades. Consequently, They would get Archer and Militia line bonuses (+1 armor feudal, castle, and imperial ages, for +3 total), and bonuses to their Archery Ranges and Monasteries (work somewhere around 10-20% faster). Villagers would also mine 10-15% faster. The unique unit would be the Knights Templar, a reskinned Paladin, skinned with a Templar cross instead of a fleur-de-lis/lion, and has 6 more points of melee armor and 3 more points of ranged armor. The Castle-age unique tech is essentially the Teutonic team bonus but a tad better (+3 Conversion Resistance, as opposed to +2). The Imperial age tech would give the Knights Templar 33% faster attack speed, but would be like 3000 food 3000 gold or something to offset how OP the Templars could become. The architecture would most Likely be middle European (Teutons, Goths, etc).
If you have any recommendations or would like to help feel free to post! constructive criticism is more than welcome.