A trophy room, showing the biggest fish of each species you’ve caught: 6
Better, customizable characters (pick your body shape, skin, hair, clothing, etc) 5, it would be nice, but wouldn't add to gameplay.
Additional types of boats (a jet boat, canoe or kayak, pontoon?) 9, I think canoe/kayak would be great for smaller, shallower streams. (if you added canoes, you should probably up the price of other boats to a more realistic level because with the canoe you could actually get out on the water.)
Additional lures and baits (such as?)8, deadbait shad for the sturgeon, stinkbait for catfish, and
Additional species of fish (such as?) 10, sturgeon, catfish, salmon, and we need a few "rough fish"
Other features (such as?) 10 with rivers, you should probably make more hazards that might make it so you have to end the fishing trip and spend some money to get it repaired (EG. rocks, logs (I saw somebody get swamped on one), sandbars, hitting shore)
Also to go with rivers, you should add some more serious snags, you can't drag a worm on the bottom without getting caught on a rock or something eventually.
New live bait rigs, bottom bouncers, slip sinker rigs, and others.
EDIT: A huge long run, perhaps a year.. or 5 in the future, saltwater fishing
EDIT2: the guide makes gameplay too easy, it could stay the same in beginner mode, but in intermediate it should give a mid- sized circle where they MIGHT be, and expert should be the same as it used to be a long time ago.