This map mainly focuses on the left side of the map, I marked the 2 rotations. You can speed up the finding of a hotspot by doing a party of 2 each have their own boat, 1 go in the opposite direction.
make sure your fishing is at 5 bars otherwise, the following will not apply to you! have a stopwatch with you every time you need to find a new hotspot, start the timer as soon as you hear your rod hits the water (not the throw sound, the sound where your rod hits the water) (turn on game sound effect), if you don't get any bites under 35s then move on.
tip1: use 10 energy as it gives you a chance for 1 additional roll.
tip2: you have a 3% chance of getting a plump, 1 egg every 20 plumps (ON AVERAGE).
I'll gladly contribute to the map with my own version that I've been working out since the event started. Looks like I already had most of the spots you had marked but I did add some of yours.