Welcome aboard! There are many answers to your questions. Personally, I love to mix it up. I make full sized, lap, and baby quilts. I love wall hangings. I do table runners, mug rugs, tote bags, and cosmetic bags. I keep some, but most are made with a specific recipient in mind. I have a ton of patterns, and I use them, but many are my own creation, or my take on something I've seen somewhere. I often change, or adjust a pattern to suit my style, or design. There are no quilting rules, or quilt police. The beauty come in that you can do what you want!
You will find this board to be incredibly informative and welcoming. Its members freely offer support and advice. You will be amazed at the talent you will see here.