Aw, Jess I think it's great that he's balanced in what he likes! Why is your DH worried about him liking something a bit girly? Doesn't change the fact he's a boy, just allows him to explore a wider variety of toys and characters.
There are two boys at playgroup who are constantly with the dolls, putting them to bed or carrying them around in the doll capsule. I think it is wonderful! That kind of role-play might make them better daddies Who knows?
DD loves Thomas, as I've mentioned to you before. She's most happy when she's playing and talking to her row of toy Thomas engines. I think it's brilliant - I love the stories, love the merch - it is such a nice change from all her pink stuff, LOL!