Clan Castle

So here is my idea/question.

A) Why do we have a wait period for refilling our clan castle?
B) Why is there a donation limit per player per request (five units max)?

If the reason is not too big of one, which it doesn't involve money (spending of gems) wouldn't it be a good idea to allow requested without a wait and to allow one person to donate say 20 troops if he wants? (A person can donate a dragon, so why not 20 goblins, or 10 minions - technically they are equal based on the fact they are given those camp space amounts).

I think this affects mostly villages whose clan mates are either not online as often, or who has fewer clan mates. If you have anyone of those issues in your clan, they would be fixed with either allowing larger donations, or multiple requests.

Thoughts?