Go the 9 footer m8
A 98L foamie will have a ton of float. I was amazed a few years ago I swapped boards with a m8. He rode my 9'4 CW longboard & I rode his 7 foot foamie. The 7 foot foamie paddled & caught waves a lot easier than my longboard, performance was another story haha but thats the next step.
For what you plan, losing weight & getting paddle fit the 9 foot foamie is an excellent choice. Just gotta get out regularly, stay focussed & eat a good diet too. I don't mean starve yourself, just eat healthy food. If its an animal, the less legs it has the better it is for you. Cut out the crap

Stick with it & you'll get there