I think it's a good idea but it should be automatically spread out to each clan member in ratio to how many stars earned/troops donated that way it for sure goes to the deserving people. Some clan leaders would not give it out to the right people
If the clan leader is an idiot, players will leave.
i dont want that the clan leader can say:
ok all gems for me horray
More like: there is a maximum a leader can give a person, like 5 gems a day. So this is less than u earn by deleting obstacles, but it would be a nice bonus.
if automaticly spreaded out, than players who donate 1000 giants are getting more than someone who donates 100 dragons, and i think 100 dragons are much more worth than 1000 giants.
Or a townhall 10 constantly attacks townhall 7 and below in clan war just to get more stars, which doesnt help the war at all