looking to get a minn kota trolling motor, just wondering what suggestions for the amount of thrust to go for ? would be on a 13ft tinny...im not a small dude 250 lbs...and the girlfriend would be in the boat as well as gear and fuel for the main outboard...and the battery for the minn kota as well i guess...so what do yall think ? best model for amount of thrust i need to troll and best battery life ?