Aikido is a very practical MA for police work. Forget the locks and pins (yonkyo is very effective when done with handcuffs). The ability to move through large crowds (weapons retention) and reading body laguage (seeing the attack) have helped greatly.
It has always been my belief that good footwork is the key. You can't build a house on a poor foundation. Having balance and awarness are always going to help you on the street, regardless of tech ability. We always highlight the fact that the real dojo is out on the street.
I take enjoyment, calm and fulfillment from Aikido- nothing else compares (well almost nothing)