Had pet hamsters years back. It sounds like you've got quite a lot of animals already. Birds aren't 'easy' pets that the stores will tell you they are, not if you want them to live very long. I think birds are more difficult to maintain than hamsters are.
Decent cages are costly too.
It was a good point too about your habits. In such a case, a rodent is a better idea. The only problem with the mice was their short lifespan, otherwise, I thought they were great pets. We had to fish them out of the furnace, from inside the sofa, and out of my mom's lingerie drawer in the middle of the night. Had pet hamsters years back.