I also really loved the Rose references in season 3, because I am a huge Rose fan and I also ship them, so I was very glad he didn't just move on, because I didn't either, so that worked out great
I get that a lot of people thought it was too much though, and that he shouldn't single companions out, but that's the way life works, you meet tons of people and some just stand out more than others. I would have felt very cheated if they hadn't mentioned her as much as they did, because in season 1 and 2 they often made a point of it to show that Rose
did mean more to him than most previous companions, and it is only realistic imho that it would take some time to get over losing her. But yes, I also felt very bad for Martha at times. Poor girl.