I must admit, I am all for an elbow that is up when playing standing. I could show you lots of pictures of me being too lazy to do it, but if I am doing any kind of "proper" playing requiring dexterity, then a dropped elbow (for me) puts all sorts of strain on my wrist and forearm. I know you are experiencing pain elsewhere but bodies are funny things and will telegraph pain from different places while they try and compensate. Keeping things in balance is imperative (maaan!). I would reccomend standing in a room with an experienced teacher. It is entirely possible that you have zero interest in playing the Bach unaccompanied 'cello suites at pitch so do not need to be paying top whack for years to come. One or maybe two lessons will give you the physical pointers you need.