I really like the rush to go for the relics in Castle Age that the Lithuanians introduced with the bonus attack they have, whether you play with or against them.
I would like to see Relics play a bigger role for more civilizations, especially those civilizations that have Monk bonuses or Monk civilization style.
The ones that come to mind are Aztecs, Burmese, Italians (maybe), Saracens, Slavs and Spanish
-Aztecs: They already have a bonus associated with Relics, but it would be great to change it based on the number of Relics your team has.
-Burmese: Add armor to the BE up to +2 -and maybe a bonus to the UU- (not sure)
-Italians: They are not a Monk civilization but it could be a nice bonus for them in some way, maybe give archers armor up to +2
-Lithuanians: Reduce the attack bonus in Castle to +2 and keep the same bonus that they have in Imperial up to +4
-Saracens: Do something similar as an attack bonus but on Camels or make Monks cheaper
-Slavs: Increase the armor to the Monks or the armor to the Siege
-Spanish: Increase the range of Monks and Missionaries with each Relic (and speed) and also give the Conqs some bonus