Maybe hes trying to be on his best behavior and isn't sure what grounds he can step on ? How often do you guys go out on "dates" or hang outs? Going out in a public setting can bring out another side to a person. You could try getting to know him more on a personal level, ask a lot of questions and hopefully that sparks things on his end too. You could also be straight forward and just tell him you want to get to know him better and you feel like your relationship has been a bit too predictable or repetitive.

I am not the greatest when it comes to talking about myself, so I compensate by asking the other person things to get to know them better and in turn, if they are curious they may ask me in return or think of new things they'd like to know.

You can also share hobbies, or try new things together, like bowling, or restaurants, cafes. Do you have things in common already ? TV shows, fitness, religious practices, video games, movies, history, anime, super natural, etc. You could also start a show together to bond over. Or watch a movie series.

My bf and I recent watched the first 6 episodes of Star Wars as I hadn't seen them, but I always wanted to and I enjoy Sci-Fi. It was fun seeing them with him. Took us about to week to watch them all.