What dog should I get?

My boyfriend of 4 years and I want a puppy to bring into our family. We already have a 4 year old chihuahua x maltese and she's a sweet heart but very timid. We want either a pug, french bull dog, or boston terrier. It's not important if their full breed we dont want to spend over 900 on it. I want a dog that I can play with because my dog is so timid and submissive she wont play she likes to cuddle and give me kisses she's a lover not a fighter. We live in a 1 bedroom apartment but its right beside a park with plenty of other dogs. Let me know what you think.