Wow, 10 rats and 10 piggies would be alot to take care of.
Rats are fun creatures. They are very affectionate and very intelligent. There is a good website for rats
www.ratsrule.com
When my daughter had rats, those were hers as the
GP"s were mine. So each, got the attention they needed. Rats like piggies do better in pairs. Their diet is abit differnet than pigs. Ratsrule has a wonderful mixture you make up for the rats diet. They love junk food (though not always good for them) It is fun to watch them hide their food or treats. I find rats more personable than pigs. Pigs could live without us and wouldn't mind. Rats love our attention. They love to be out with you and love to explore. You can train rats with mazes and some tricks. Rats to not use balls or wheels for exercise. They are not skittish (unless mishandled) have great personalities. They are great fun critters.
Rats do not live long lives. Average is about 3 years. They can be prone to resperitory infections and tumors. My daughter loved her rats, but had trouble with the short life span. When one died she was heartbroken.
I think if you had a couple of each, rats and
GP's you could spilt your time and be ok. but much more than that I believe you would get overwealmed as each have time requirements.