Currently the MiBs are a bit buggy, but they do provide a good bit of gold (couple thousand in depending on the crate).
The other goal of fishing is to pull up a) cooking ingredients and b) pull up rare fish for the (upcoming) fish tank house add-on.
Fencing does get a nice boost form fishing since you can get to 120 fishing which would = 120 fencing when using a harpoon on a boat.
Discordance is another good skill to add and is the only barding skill that works on the seas.
If you're only going to be doing fishing with that character then probably this template:
100 resist
100 anatomy
80 healing
120 fishing
100 tactics
100 tracking
100 parry
This will let you solo the mobs that get pulled up with a crate or a net.
If you're going to be doing ship vs ship combat then I'd recommend a summoner mage.
100 Magery
100 med
120 Spirit Speak
100 Herding
100 Eval
100 Fishing
80 healing (for healing your crew after battle) or 100 tracking if you want extra damage and can find the skill balls for cheap (currently ~40k each)