If you remove episode 3, I think the first half of the series is quite good. You just have to be able to follow and understand the design behind how characters are introduced and developed. The second half though, after the big time skip, however, I found to be completely mundane. If I remember correctly, I started the series with a 9, then dropped it to a because of episode 3. It climbed back up to an 8 until the time skip, where it dripped to the 6 it remains to this day.
I would refute it having many plot holes or much incoherence (I actually consider its predictability to be one of its flaws), but this is neither the time nor place, especially since OP is going to give it a go! When compared to majority of anime, especially recently, it’s still of considerable quality (though that’s not meant to be saying much).
@crihak, do tell if you enjoy 新世界より, as I’ve found many anime series I’ve disliked, especially in the way of pacing or story telling, I often enjoy after reading their source material. I have a bit too much reading material on my plate currently to pick it up though.