Mercenary guild

Hello everyone! My name is Victor and I play coc for a while now, and I had an idea that (in my opinion) would make the game more interesting....

My idea is the creation of a Mercenary guild. I know (and I read) some posts before about this, but any of them was like mine (or as complete).

So, here is my idea:

Imagine if you could hire mercenaries to help on your attacks and defending your village? That would bring you more units, more diversification of troops, more options and more fun. =]

So, to explore this better, I divided my idea in three topics: building, units, costs of building and training

1 - BUILDING
I thought this building as a tavern, that is historically a place where people went to drink, gamble and... Hire mercenaries! I'll talk more about this on my last topic.

2 - UNITS
for now, I thought of some units... As mercenaries are warrirors coming from far, i thought of these units having exotics caracteristcs.

a. Sailor - a basic unit, something similar to the barbarians, but... Sailors!
b. Assassin - a unit with a mask and a tunic. Has advantage over other units (x2). On attacks will have advantage over heros and units on the clan castle. On defence, will have advantage over units attacking.
c. Xamã (or black wizard) - I thought it as similar to the hogh rider, but not mounted, bald and with some exotic characteristic (tatooed face or something). Has more life but lower attack.
d. Imp - a dwarf dessed in green that spells Random Spells on friendly units (healing, fury, wall jumper)
c. Mounted Elf - an elf mounted on a skelleton dragon that breathes ice

3 - COSTS OF BUILDING AND TRAINING
For this topic, I have two suggestions (suggestion because Supercell has better knowhow on monetizing this):

a. Training and Building with gold
On this case, the Mercenary Guild would behavior like other training buildings, but instead of using elixir, it would use gold. So the trained units should be stored at camps, will have time to train and can be donated to your clan folks.

b. Training and Building with gems
on this case, the building would be constructed with gems and the units would be trained with gems, all of them instantly, without the waiting time. The units can't be updated on the laboratory.
As the game gives the user SOME advantage for players that use gems, this option should also give the user only SOME advantage. So, I thought it storing the units on the Mercery Guild after trained. This way, the user will have a limited number of mercenaries to train. On the other hand they could also help on defending the village against attacks (like the clan castle).

This is my idea! Hope you guys like it and help me to make it better!

thanks,
Victor