Pros
I think your experience at WB is largely dependent on the team/production you're a part of. I happened to work on a production that had a significantly healthy working environment with friendly and reasonable coworkers. Our line producer advocated for us and I've been able to negotiate for raises between seasons.
Cons
Hiatuses are an expected part of the job – when you're done boarding a season of TV, there's no more work for you to do. In my experience, I've seen that WB Artist Management makes an effort to keep as many artists on staff in some capacity as they can, but the industry is particularly dry as of March 2025 and the recruiters can't manifest jobs out of thin air. I personally attribute this risk-averse strategy of greenlighting fewer productions to the mismanagement of the WB brand and the fallout of 2 nearly back-to-back mergers (first AT&T, now Discovery). Also, from what I understand, WB pays less than other studios for similar storyboarding work.