Fishing is great and I would love additions to the mechanic of it. But what you are describing are rewards associated with fishing, not the activity itself.
I'd love to see additions of different types of rods, lava fishing, different types of bait, and a fishing rework that turns into into a mini-game that requires player input and activity (which would then also break the standard auto fishing mods).
On the other hand, just increasing rewards for fishing, leading to people feeling like they have to fish, or that automating it is going to be very profitable, instead achieves the opposite for me. There are other knobs to turn to improve fishing as an activity other than just increasing the rewards for it repeatedly.