The old system was not better, it was more flawed than the current one.
The old system only befitted the high level and strong players and also encouraged and gave advantage to the GPS cheats. A larger section of the playing community had absolutely no chance of collecting any coins at all.
The best counter to both systems is you get your coins for Gym engagement. You put something in you get your 10 coins. You don’t need to hold it in there for any period of time or have to wait for it to be booted.
The only rules I’d apply on that system is you can only collect off the same Gym once every hour to stop people with multiple coloured accounts hitting one Gym continually swapping between the 2 colours in 10-15min. This is to encourage players to hit other Gyms. This could be a problem for regional or small towns that have less than 5 Gyms. The compromise to that would be to have 2 ways of collecting. The current time in and collect upon return in conjunction with just put something in.