First of all, the cast is a bit more diverse than most shows (but pretty on par with the other WD shows). And while this show has some major shortfalls, that is definitely not one of them. So it's really sad that some reviewers have specified that as being the reason they don't like the show.
Anyway...
I'm 29, and it's clear that this show was written for a younger audience. Maybe 14-17 year olds. The reason I say that is because the violence is toned way down from TWD, and a lot of the themes revolve around issues that teens would probably be dealing with. Maybe when I was 18 and started watching TWD, I would have connected more with this show, but I'm definitely closer to having my own kids that having parent issues! XD
I only finished the first season, and I think they did a lot of interesting things with the characters' growth and their backgrounds. Some of the acting is pretty bad (mostly the younger actors, although the kid that played young Elton did great, imo), and the dialogue is corny. There's a bit more "why did they do that?", "that doesn't really make sense", and "they changed their mind pretty quickly, huh?" moments than the other shows, and it does get distracting. Like a lot of others, I find it a little irritating that the teens are terrible around zombies. However, I don't blame their characters so much as others seem to, because apparently the adults in the town they grew up in were morons who wanted the kids to have "normal" lives in a very abnormal world and never exposed them to the 100% real and ubiquitous threat they would certainly run into one day.
Overall, it's more of a show I've been putting on in the background maybe while I play Switch or something, hence the 3 stars. For long term TWD fans, I'd recommend doing the same just because this story is canon and might connect with the main show. Younger viewers, however, who haven't seen any TWD might like it and use it as a bridge to the others shows.