Back in the elder days, controllers tended to be big, heavy things, and even the best ESCs lost significant power. Nowadays, there are forward only ESCs that actually weigh less than the servo that would otherwise be needed, and can handle considerably more current than most microswitches. They also, with a bit of shopping around, probably cost less than a servo and switch. Only caveat there is, if its oriental, take their amp figure, remove a zero, think of a number and divide by that, and you will be about right for continuous use in a boat. Most of these ESCs were intended for flyboys, and these invariably have lots of moving air to cool them, not so inside a hull.
A fast boat is considerably less resilient than a concrete bank, so proportional control is better than on/off when bringing the boat in.
Reverse, while not much use out on the water, can be useful if you manage to go aground or get into a tight corner.