I don't know if this has been suggested before since the search never works, but here it is. Basically, Minecraft should not allow eddies/whirlpools to form in large bodies of water (maybe 3x3x2deep or greater). My lakes are all full of eddies from people taking water, and they should refill! Water flowing in a direction at the shore is OK, but water flowing into a whirlpool in the middle of a lake is just messed up. If it is 3x3 or greater and 2 blocks deep or greater, it should not form these whirlpools.
Support shields replacing parrying here! (Click it)