I've fished BFL's as a co-angler for a number of years. I have some experience in this matter. 3 rods probably aren't enough. 9 rods are probably too many. Every time, the deciding factor in what to bring or not is how big is the boat that you're fishing out of.
Are you fishing as a team? Are you fishing against your boater as well as everyone else? If it's the latter, I'd find a new club. If you are fishing against the guy you're sharing the boat with, sooner or later something bad will happen. That is a situation to avoid.
Fishing as a team, ( or as in the BFL, there are two different pots.) it becomes a different story. Communicate with your boater, find out the plan for the day and pack accordingly. Some guys who fish as a team all the time share everything. That greatly reduces the number of tackle boxes in the boat. Other guys will say they will share but after you've dug through all their stuff looking for a weight or some other obscure thing, they are not so hot about it. With good reason.
The point is to find a happy medium to where you're not feeling handicapped with a minimal amount of equipment and he's not tripping over all your stuff in his boat.
Try to make good use of the space you've got. If there is a seat on the back deck, get some heavy duty velcro straps and strap your tackle bag to the seat. Then you'll be the only person tripping over it.
For me, an inflatable life jacket was a good idea. I just wore it all the time and I didn't putz around and waste time when we were getting ready to run to a different spot.
Some rods can serve double or even triple duty. For instance, a flippin stick is also a good carolina rig rod, and also works good as a bubba drop shot rod.
Your spinnerbait rod also works good for throwing square bills into bushes and laydowns. There are lots more instances where your rods can do double or triple duty.
Know what your primary approach and principle secondary approaches will be and build from there.
Bring enough soft plastics, but don't go nuts about colors or quantities. Brink enough crankbaits and jerkbaits, but you probably don't need 30 of them. That being said, should there be something that you think will work on a particular lake, be sure and bring it.
Fishing as a co-angler, you need to be more organized. Money spent on bags, and boxes and other organizational gear is money well spent.
In alot of ways, fishing as a co-angler is harder, but in lots of other ways it is much less of a hassle. At the end of the tournament, you drive home and don't have to deal with all the boat issues.