not to go all "back in my day," but really, stop complaining, it used to be a lot worse.

i did 0-70 under the original system, and at one point went three weeks of fishing every day for minimum 4 hours a day, without a single skillup.

if you're getting a majority of monsters/items, you're doing it wrong.

go to www.finalfishing.com and use the database to find a rod/lure/bait appropriate to your skill level. their database is up to date up to WotG (and if you're still skilling, that means it covers any fish you can catch).

showmo is absolutely right, fishing is the only craft where you can make money skilling up at all times. do you have a lu shang's? if you don't and your skill is higher than 35-40, stop what you're doing, and either start fishing moat carp every day, or find a fish that either sells well on AH or NPCs well and fish those and buy your carp.

but honestly, just do some research. if you're only interested in skilling, find a fish that's 10-20 levels higher than your skill, that bites a lure (so you don't spend money on bait) and won't break your rod/snap your line and just fish. you are literally pulling gil in with every fish.