friendly challenge improvement

I take that friendly challenges is a feature for practicing your attack strategies.
So i thought of an improvement that could help

Since friendlies are a way for honing clan members attacking skills maybe why cant u make them choose a virtual army before attacking.

By virtual army i mean someting like selecting which all troops and spells u want to select for that friendly(out of the inventory of troop and spell that player have unlocked) , without any training time delay or cost be to be used just for that 1 friendly.

That would help players test out their attacking strategies better easier and faster, because as of now we need to train an army with ressies and it takes time . So if we need to test out another army either we have to use it out in multiplayer and cook again the troop we want and wait for more than 30 minutes and again use up the resources or disband the troops to reconfigure the army again at the cost of loosing ressies.

So if you could select a virtual army right before attacking a friendly challenge you could test the army composition you want without any delay or wastage of resource.