Mentioned many times already...Key to getting coins/gyms is to be the "last" (late night) gym taker and collect 6+ hours in the morning...Ideal if you have 6 accounts to deter casuals by forcing them to fight 18 fights minimum...
Sadly, I don't see them changing things back so I agree that in a month or so, casuals will be bored with the raids (my wife is already bored and feels forced to use her free pass) and hardcore already are pulling back...
The change has also made levels irrelevant (lvl 5s can get level 20 Tyranitars now if raiding in a big group), hatching eggs, buddy candies (rare candies are far easier to get than walking 5km for 1 candy), high IVs, leveling, walking, exploring far and out of the way gyms are all completely pointless...I see my favorite, undriveable gyms with the same players sitting there for 5 days...rivals won't bother attacking to reward you and players have limited/no incentive to hike/walk anymore to far off places.
Also, 75% of the mons (defenders, prestigers) are now even MORE useless and gym diversity isn't any better than before IMO...(always see Blissey, Snorlax, Dragonite, Vap, Rhydon, Gyarados in gyms now)...
They solved nothing and gyms will stagnate even more since I'm even less motivated to kick our rivals and REWARD them with their coins for the day...esp when I will be kicked out in < 1 hour.
I just play to try to solo Level 3 raids (building my team) now (Lvl 36+, used to collect 8-10 daily, free2player) and hope this gym rework is completely tossed out (very doubtful and IMO worst than before)...