Ratties Thinking about adopting

I have 3 guinea pigs and 2 cats at the moment that i spoil ohhh sooo muchlol They are deffinatly enough to hold my attention, i have just been thinking about adopting rats. I had a pair when i was younger and have been doing lots of research on them. I have an appropriate cage already and have almost all the essentials i would need i even found a few babies on craigslist that were an accidental litter i may adopt. Really my main question is the diet. Ive read all different things to feed them. I was thinking of doing the senoir dog food and somewhat of a Sue Bees diet. As well as a small amount of veggies everyday. So my question is i will be most likely be getting a set of baby males. What is the best diet for their gender and age. Also i would love to know how other people feel as having rats as pets.