well my advice is to be thankful that your even catching some in the day, that can be hard to do sometimes. big ones can be very hard to come by in the day, cuz they are lethargic. that causeway looks like a great spot. just like people would use it as a road, fish will too. they can use it as quick access to different types of structure or cover and even quick access to different depths. that reallly looks like a great spot you got to yourself. a real untouched place. if youre using powerworms with success, then keep doing it! why ruin a good thing right??? but, you could go out and buy some gammakatsu offset EWG hooks in 3/0 size, and pick up a pack of YUM Dingers why your at it, and rig those tesas style, but on the dingers, theres a little hook slot, so you can put the hook point in there so its exposed, but since its in that slot, its still snag free. just cast out those dingers, let them sit for a long time. then just shake your rod tip, reel in the slack that creates,wait a few more minutes, and repeat. there are so many different ways to fish a YUM Dinger. go here http://www.bassresource.com/bass_fishing_forums/YaBB.pl?num=1121527643 for the motherload of information on this bait and how to use it!
hope im being of help to you! feel free to PM me if you need anything.