I also thought that fishing is gonna be in. Why not make fishing spots in rivers and ponds marked by swimming fish or bubble ripples that work the same way as conainers, and from which you can randomly get a fish, loot (like old boot, bag of coins etc) or nothing?
That's practically identical to what Torchlight 2 has. The difference is that there was no crafting in that game yet it still had fishing as a side activity. There was a limit on how many times you could fish in a hot spot, and it would disappear after 3-9 casts.
Sure it was simple and there was no -fishing- skill, but in DOS it would have a gameplay purpose besides being "roleplaying fluff".