When you don't include the original creators in a reboot, you're bound to trip. While the animation is good and very entertaining, the writing is its biggest weakness. The show drags out the "hey, we're a reboot!" gag throughout the entire season. It's fine for the first two episodes, but beyond that is stale. I was also disappointed by the lack of time travel. Rather than visiting different events and cultures in history, we're stuck in current year. Lastly, there's way more partisan political jokes. The original made fun of everyone and was only a small portion of the humor. Bill Clinton only showed up a couple times in the original, while Trump shows up at least three times in the first season alone. The Animaniacs are basically anarchists, but the episode "Bun Control" was a very blunt message telling the audience what to believe. That's a good way to alienate half your audience.
In conclusion, for a reboot it's all right. Warner Bros. leaving out Tom Reugger was a mistake. Tom's on the record saying his agent contacted them when he heard about the reboot and Warner said they didn't want him. Big mistake.