I'm sorry to hear you started your trial before the season's all out. I think that the service is a good value for comics fans, but not so much for more casual fans who just want their Batman: TAS and Teen Titans. Frankly, I think it would be prudent for them to add a cheaper "just movies & tv" option.
But anyway, about YJ S3 (having seen the first six episodes) --
I am thrilled with the set of characters they're introducing, especially this version of Brion Markov. And the title sequence for each episode is just so... chilling.
My only concern is that we're probably not going to see nearly as much of Blue Beetle as in Invasion.