I have a tandem sit-on-top 75 lb kayak. I live in Fl and generally kayak on the bay or down easy-flowing rivers filled with trees that must be navigated around/under/over. I want a kayak that is light weight, single seat, easy to paddle and does not have much storage. I am not all that strong so I want one that will be easy for m to keep up with a kayak group going down a river. I also don't want to pay more than $400. What would you suggest?