I have had two great matches so far. I have been playing forever as well and have clearly built up some characters that don't help me too much anymore. My focus for the last year or so has been on usable teams though - so that gives me a chance.
I have had good conversations with my opponents, we talk about strengths and weaknesses, and so far we each see how we could have won if we had made one less mistake.
The rewards will be better when the full GA goes live - season 0 was just a 1 v 1.
Great experience so far (bugs not withstanding)