How to fix gyms in 4 easy steps

1. You can still spin the stop, it's on bottom right. (edit ah I didn't try to interact with the gym after I won the fight, sorry).
2. Yeah, the feeding thing became moot when it never helped us recover the mons from the gyms unless a rival attacked them.
3. It's been suggested heaps of times, but some players said that it would encourage multi-accounts / shaving. It would be better if either they allowed mons to get 50 coins claimed per each day without coming home (gives an incentive to enemy teams to stop them from it) or allowed mons to be recalled after a certain time (8 hours or 24 hours) and the coins come with them.
4. I'd rather they just restore the old system, but keep it at 1 member of each species per gym.

Still think that's not enough stardust compared to what ppl used to get... 100 stardust is the same as catching one Pokémon. Battles are more time consuming and take more effort to do (have to go to the gym, choose attackers, wait during battle screen, etc.)

I am sure, niantic is working with high preassure. They have statistics how gyms work now, in rural regions, in big cities. They work on a solution that fits for the most of us.

Yes, many of us have got many good ideas. Most have their own situation in mind, not the many different regions.
I am sure, Niantic is reading here and in other forums too, they know the problems many players have.

Let some time go, they will find a way.

1. Raids don't block out gyms. After beating a raid boss you should at least be able to spin the pokestop.

This will not solve a single problem.

2. No more feeding Pokemon. Training battles increase motivation instead

I am glad that this unintuitive "Training" is gone now. I am glad to have something to do with my superflous berries.
Your solution does not solve any problem.

3. Rewards for winning battles against enemy gyms. 1 coin and 100 stardust per battle won. Capped at 50 coins and 5000 stardust a day

This sounds good. Will force some action. Maybe too much dust for such an easy task.

4. All Pokemon lose motivation at the 3000 cp plus rate of 10% /hour

Would make sense in combination with them coming home after having lost their motivation.