I'm in the the 'do less challenging patterns' camp. I'm still learning and not terribly accurate, but I have lots of fun and make pretty things. I usually do tings like D9P or a pattern called Coconut chips that was a lot of sewing wide strips together and then cutting them in slices and sewing them together again. You can make very pretty blocks without having to be super accurate and stress about it. Why not just do some working on your own with things you can be successful at and leave the more challenging stuff for later?
That said I also agree with having someone experienced help you. Often someone else can spot your problem areas. I also agree with trying different devices to help with your quarter inch seam. We have have different things that work for us. Maybe you just haven't found yours yet? Does the quilt class you've joined have an instructor that you can ask for help?