Lost all the fat desired, want to improve muscle quality...

I have been maintaining my goal weight for 2 months. My muscles are bigger and more well-defined than they have ever been in my life. Nutritionally, can anyone tell me what to be conscious of, as I am trying to define my nutritional values for a lifetime now, rather than for weight loss? I know that as my body changes, if it does, I would have to re-evaluate. I am conscious of protein intake, however I wonder what else I need to think about. Do I need to worry about iron or B-vitamins? Do we need extra calcium to support extra muscles? What about fish oil for joints? Tell me your tips. My muscly body is different than my flabby one, so I would like to care for it properly.

Thanks,
Voodoo Lady