I run the LL Bean angler edition Manatee kayak. I'm not 6'3", but I'm 5'8" and have plenty of room. The opening on these are pretty large, and overall, its pretty comfortable. I was out for 6-8 hrs this weekend both days, and took minimal breaks to stretch my legs. There are 2 built in rod holders in the back, and an adjustable one in the front. I don't really use the front one though because it gets in the way.
I also run 3-4 rods every time I go out, so 2 in the rear holders, one between my legs and 1 that I'm casting. It's usually not that annoying. There is plenty of storage behind the seat, and I usually take a few of those flat plastic lure boxes and put them on each side of the seat. I keep a life jacket crammed in there too ( when I'm not wearing it), which holds my line cutters, camera, scale, etc.
The American Flag is an aftermarket addition, that is well worth it...although I would recommend a smaller flag.