help I'm a step mom and don't like how my step son is being raised.

my husband has a 6 year old from a previous relationship. I love that little boy, but because my s.o works out of town and the mother of his child has more custody of his child I hardly ever see him. my mil would never tell me when she had my step son until I put my foot down and told my s.o I was his wife and should be able to see his child when he's supposed to. I finally see him whenever, but the problem is how he is raised. I hate how my s.o and the m.o.c raise his son! my s.o sees no fault in how he's rasing his child that I'm worried when we have kids he's going to be doing the same things I don't approve of. he lets him get away with things without disciplining him because he hardly sees him. so he goes unchecked when we have him. I honestly don't know how to bring it up because his son is such a sensitive subject. should I just wait till we have kids and bring it up then or tell him now?