You can't compare Mining and Botany to Fishing, they use completely different gathering systems and has a minimal impact on the game as 90-95% of what you get you have to NPC sell as they have no place in any crafting class.
Take a look at what you have between the classes.
Mining & Botany
You get to choose what you want to gather
All items can be used for crafting or placed on market
You have abilities that influence your gathering
You only have two tools
No fatigue system
Fishing
What you get is influenced by your bait but is otherwise totally random
90-95% of what you catch has to be NPCed
You have 0 abilities, GP is a total waste on this job
You have 1 main tool and about 2 full inv screens worth of bait
After a few hours of fishing you will be locked out of that fishing spot (no idea how long)
Just last night I had to buy 5 full stacks of rat tails just to get 1 full stack of clams and oysters to make some soup for crafting CP, it was hours of grinding that I could have probably done in 30min to 1 hour on either botany or mining if that was possible.
If SE goes though with this they are acknowledging that what Yoshi P told us was incorrect and fishing is actually a full fledged gathering profession that must be equal between all gathering classes, in which case the door swings both ways... equal the xp gain between the three than you have to make fishing behave EXACTLY like the other two gathering professions.
1. Let us select what we want to catch, influenced by gathering and perception skill
2. All fished up items are to have a place with in the game / economy, in other words bring back all the crafting recipes you removed from v1
3. Put in Place GP skills to influence gathering
4. Give us an off hand item, as many have asked a fishing tackle box to place the screen full of baits in and out of our inventory
5. No fatigue system
This game is ridiculously easy with its major shallow xp curve and if anything the entire game needs an xp nerf to bring it back in line with the curve from v1.