Superline is fine. Just keep tension on the fish, you'll be fine w/o barbs.  15lb is fine.   You might want to pack a spare spool of line, or a spare reel in case you hit some major twist issues.

Unless the water is gin clear, go ahead and tie directly to the lure. I'm a fan of the palomor knot with superlines.   If the water is clear - you  might want to look at a fluro leader.  Make sure you've got something that will cut the superline (nail clippers aren't so good - I use the superline scissors).

As for lures - add some 4" swimbaits (with the thumper tail), and jig heads. A few safety-pin spinner will turn them into spinner baits.  I think I'd include a white color and some more perchy colors.  Given the time of year - I think you'd want to go 1/4 oz and heavier to get them down to the fish.