2 nights a week and every other weekend is not too much. My stepson we had him three days a week and every other weekend for years. Basically since about 4 months old, when his parents divorced until about 5. at 5 my husband started working days instead of nights. we swithced to 2 days instaed of 3, since one of the days was a friday, and it became difficult that neither family could do anything firday nights. both us and his mom go out of town during the summer a lot. So we chose 2 nights for tht reason.
an infant needs both parents. its as if you are saying that if you were togheter, your child wouldn't see the dad that much, becasue it's too much for her.
You have to do what is best for the child. it is difficult at times, but the child needs mom and da din their life as much as possible. so if he is offering to takke her another night go for it.