I agree with Pescatore all the way. The only other thing I would include is to stay away from the heavier 4-stroke engines and stick with 2-stroke if maximizing shallow water performance is a priority for you. The major downside of sticking with the 2-stroke is an decrease in gas mileage and an increase in noise unless you go with an E-tec (Evinrude). The E-tec is probably your best answer in finding a happy medium regarding power-to-weight-ratio and gas mileage. The E-tec has virtually no maintenance for the first 3 years or so, BTW.

If you could ever find a nice deal on an inboard jet rig, I would jump on it. JMO