I've done what has been described as "full on invocations" before, but I think it'd be great to swap notes and get training with people who can help me to improve those skills and teach me things I haven't heard of before.

I've learned quite a bit working in groups and I agree that you can learn a lot in that regard, but you can't possibly run into every scenario within a small group. Some, yes, but not all. Hence why I want to get more formal training.