As a blink-182 fan who has been listening to them since 2000, I'd like to say California isn't great but it isn't bad either. There are songs I love (Hey I'm Sorry, Los Angeles, Home, Left Alone, San Diego) and songs I find absolute trash (Sober, California, Rabbit Hole & TOTTM). The other tracks I just find average or solid.
My gripe with the album is that it simply doesn't sound like blink-182. My favourite album is the smiley face album, which at the time didn't sound like blink-182. The difference IMO is the smiley face album to this day is still so original. No band sounds like that at all. No band has done a sound like that except blink themselves. California mostly sounds like songs rehashed from All Time Low, Fall Out Boy, Panic at the Disco, Good Charlotte and heck, even Paramore and Busted. That's what I hear. Like Oliver, I can't stand all the WOAAAAH or NANANANANA crap. I don't mind it every now and then, but almost every song is boring.
There are even AVA tracks that I find better than all the tracks of this album. Keep in mind I do not like AVA much. I believe that's a band with great ideas that fall flat. Neighborhoods has its trash songs too, but its best songs are better than anything on California IMO.
I'd rather blink-182 come up with something totally different and make that sound their own, like they did with the smiley face album. California doesn't offer that apart from maybe two tracks, which isn't enough for my liking. I too would rather blink avoid Feldy for future albums. Blink doesn't need Tom, but it also doesn't need co writers and producers coming up with everything. I'd rather a producer just let blink be blink, then work on the great ideas in order to reach full potential rather than fall flat like AVA.