If you have to use your big motor to troll, you might pick up a drift sock to help slow you down. Or make one with a bucket. I prefer using my troller on twain because there a lot of stick ups along the banks and I'd hate to ruin a prop.
Don't over look using those 200's without extra weight. 300's and wiggle warts are my favorite for twain. Might run a couple of your lines a tad farther back behind the boat. Might try closer, too. Luck!