I did a lot of blankets when I was first starting out. Granny squares are pretty easy to make too and you can either sew them together to make a blanket or they can make good coasters or pot holders depending on the size you make them and the kind of yarn you use. Also they crochet up super fast so it's like instant gratification and they can be as simple or complex as you want to make them depending on your skill level. You can find whole pattern books devoted to them with endless variation.