It would be a nice addition if along with the ability to train new troops, upgrading the barracks trained lower units faster. Ex. The level 10 barrack trains
Pekka in 45
dragon in 20 mins
Healer in 10
Wizard in 6
Ballon in 6
Wall breaker in 1:30
Giant in 1:30
Goblin in 25s
Archer in 20
Barbarian in 15
Available at barrack level 8
