The main crit I have Steve is the fish itself...

It's too shiney and too dark in colour. Salmon filets have more of a dull sheen to it and a lighter pink/peach colour, and tbh I would use a lambert or a modified blinn for it... I dont think it looks like wood at all tbh, its all tweaking and lighting as you said. Oh and the bumps are very good, and sit well with the surface...

I think the render reminds me of an oil painting... Now that cant be a bad thing... Good work anyway m8