Stronghold Towers for Persia (and maybe Celts)

Hi everyone, if it wouldn't be too much trouble, I think it would be great to re-implement Persian Stronghold towers into the game. The model is already there, and so is the upgrade. In 2011, it was a normal upgrade that you could get as Persia, but it was removed. I cant think of any reason why, as they aren't over powered or anything - Greece would still have the strongest towers, and Persia was meant to have them as seen here at the 15:32 mark.

Persia is very difficult to play on certain quests that require heavy fortifications because of this removal, and they would be a good addition. Furthermore, as it's all just PvE, it wouldn't really change any balance.

I know the Celts also don't have the stronghold upgrade, but I believe they never did, nor were they meant to, as they also have very weak walls and are meant to be very aggressive. Again, it wouldn't be bad if they did get them, but they never had them in the first place so it makes a bit more sense.

We already have the assets, and even the upgrade, it would be great to see it available.