Upgradable Builder huts

Maybe if you could upgrade thier speed. Make thier huts be the same though.
Lvl 2-
Price- 6,000,000 Gold
Hitpoints added- +10
Time decreased-10%
Lvl 3-
Price- 7,000,000 Gold
Hitpoints added- +15
Time decreased-15%

Lvl 4-
Price- 8,000,000
Hitpoints added- +20
Time decreased- - 20%

This is just an idea. A work in progress, any ideas please comment. Thanks guys!

Hi, upgradable builders is a ruled out idea; please see the sticky: http://forum.supercell.net/showthrea...rum-guidelines