Gym coins are horrible you should get more than 50 a day. If you have a crap load of gyms taken over, and you worked hard you deserve to get all the coins for the time they are in. So once they come back you should get the 50 for that hour, and if its been two days then a limit should be per Pokémon. So say one Pokémon is in a gym, that Pokémon should be limited to so much a day once its returned, but it there shouldnt be a limit on all per day. You should be able to get 50 per Pokémon in each gym a day. So for ex. If I have 3 Pokémon in a gym for one hour its 150 coins, so if 1 Pokémon is in a gym for a whole day the max coins should be like 50 to 100 per Pokémon so we arent losing our effort, and time on gyms.
Don9690 about Pokémon GO, v1.39.0