I am in a non-competitive family alliance, I am not the leader. We also have a few log in-request-log off folks and users with zero trophies. Some lineups do not change in spite of them receiving donations. Some people always request in-demand DNA. As a member, I choose not to donate to some other members due to what I see.
There is no way to follow who is donating what, none at all. I am hoping for at least minimal tools for the leader in 1.6.
As a member, I broadcast what I have available for that day or the week. Mostly it is Stego, Ankylo 2, Ophia, Tanny, Suchomimus and such as I am an L4 park player. I will fill all requests for them. I will not donate my hard to get or valuable to me DNA. Sorry. I look at it as I can fill a niche in DNA donation, I have access to something of value to others who cannot find it. If I had an abundance of Utah or Posto I would do the same, but I do not see many rare, only the park commons.
I look at it as sharing local spawns with others in different locals, not helping someone to build an entire team. Other, competitive alliances most likely look at it differently and strive to help people achieve those stronger teams by donating till it hurts.
I do not request DNA as there is nothing I really need. I level up what I can find, to me that is part of the game. For me, an alliance is all outflow, net loss, no gain. I stay in to help folks with DNA I have an abundance of. I also see them having a benefit later on in the game, so will stay in one. If the members took a poll as to if I donate at all, many would say I never do and a few would say I always do. My donations are not spread across the board, only to those who request what I have in excess. I know the members who are getting 400 Stego twice a day are pretty happy with it.