More than waiting for bags, there can be considerable deviations from the arrival time depending on winds aloft on your particular day of travel. I've arrived up to an hour before or after the "scheduled" arrival because of this.

Passport control is fast, baggage 15-30 minutes depending on how lucky you are for getting your bag early in the process. I usually don't check bags and can be out from the plane, through passport control and customs (never been stopped for customs in dozens of trips) in maybe 10 minutes.

If you miss your train, don't sweat it. There will probably be another one you can take within an hour and you can probably use your ticket, though you'd lose any reserved seats. That usually is also not too big of a deal either. Just grab a seat that is not reserved for anyone and usually there are plenty of those, except perhaps Monday morning or Friday afternoon/evening.