This is an Idea I had for a while, however because of the recent patch, This would make Burgundians OP and I can no longer justify it without undoing some of the changes which I think are mostly justified. I would give Burgundians to build building one age earlier than generic civs This would allow Burgundians to use some unconventional build order. The ability to would allow to build production buildings early and be able to produce units as soon as they reach Feudal/Castle age. it would also allow for a better fast castle time as you could build a market and blacksmith in the Dark age. Like the Khmer bonus this it is nearly useless unless if you're playing conventionally but would allows to do thing that no other civ could. Now to address the elephant the room, the ability to build Towncenter, Towers, and Castle one age earlier is blatantly OP, Unless they are nerfed into the ground until you reach the next age. This would only apply to buildings they build, not building that they get at the start of the game. Alternatively the bonus could not apply to building that require stone.
Dark age Towers:
No bonus dmg
Build time: 100
Hp :400
Range: 5
Accuracy: 80%
Rof: 2.5
Los: 7
Armor: 0/4
Fuedal Castle:
No bonus dmg
HP: 2400
Build time: 350
Rng: 6
Los: 9
Accuracy: 85%
attack: 8(2) unable to fire more arrow
Rof: 2.5
Armor: 3/6
Feudal town center
can't create vills or research
Promotes upon destruction of starting TC
Build time: 270
Dark age Towers:
No bonus dmg
Build time: 100
Hp :400
Range: 5
Accuracy: 80%
Rof: 2.5
Los: 7
Armor: 0/4
Fuedal Castle:
No bonus dmg
HP: 2400
Build time: 350
Rng: 6
Los: 9
Accuracy: 85%
attack: 8(2) unable to fire more arrow
Rof: 2.5
Armor: 3/6
Feudal town center
can't create vills or research
Promotes upon destruction of starting TC
Build time: 270