Dark Builder Huts

My suggestion is -- Dark Builder Huts!

So heres what it would be:
Basically a Builder Hut except it can only help build and upgrade dark buildings and defences. However the benefit would that, depending on the level, it upgrades/builds at a faster rate.
However these builder huts would only be unlocked at town hall 8 or 9 or whatever.

Some ideas for it:
Dark Builder Hut #1 - 1250 gems
Dark Builder Hut #2 - 2500 gems
Dark Builder Hut #3 - 5000 gems

Level 1 Dark Builder Hut - x1.25 normal building rate/ 1500 gems to upgrade to next level
Level 2 Dark Builder Hut - x1.5 normal building rate/ 2000 gems to upgrade to next level
Level 3 Dark Builder Hut - x2 normal building rate

~Thank you <3
Blizz

Sorry, this is a modified version of a long ruled out idea of upgradable Builder Huts.

Except you are asking to put in huts that are upgradable, rather than make the current ones upgradable.