As a suggestion, if at all possible, I would refrain from cutting the fish into steaks. You never quite get 4 steaks per fish and the points you get are either 1 point per 4 steaks or 1 point per fish. If you can transport the fish on a pack horse, pack llama, or blue beetle, you will get to your goal quicker.
Also, I would take any money you make from fishing and buy the fish from fishers. At 15 gold per point, you would have to buy fish at 15 gold per fish. I usually see fish sell on NPC's for anywhere between 3gp up to 8 or 9gp. So, if you were going to take this route and buy the points, you're still better off buying the fish and turning the fish in.
It takes a long time though...
Good luck,
M.B.