If you want only certain troops (what you always want because you nearly never want wb lvl 1) than I think it would be an easy way, to set all the troops you want to get in the cc, so nobody could donate wrong troops. The first time it takes perhaps a bit but you can save 5 different troop panterns which you want to get, and each time you request you choose the pattern ( for example: only max archer, wizzards 5, dragon 3,... ) then only these troops can get donated.

