So I read through all of Beelzebub, and it was... interesting. It kind of reminds me to Ranma with its specific balance of gags and fights, wherein it's DEFINITELY a gag manga, but it does shift into serious (or "serious") battle manga stuff frequently enough. I'd actually say it probably leaned a little heavier on the fights then I liked, though, as frankly it was kind of weak at those generally. Like, it had its moments even in that regard, but I don't think its battle moment bits are all that strong.
Also, man, again it doesn't matter as much because of the heavy dose of gag focus, but the overarching plot stuff and character development (for the most part, especially when you got away from the core cast) was just plain messy. Like, it almost felt like freaking Bleach or something in that regard (still more competent in pretty much every aspect, and affected less by this issue as mentioned above, but still... so many ideas and plot points and characters with little to no payoff.)
Btw, did the series get rushed to a conclusion, or no? Like, it really felt that way as the final fight kicked off and ended so damn suddenly and was a real step down from the prior arc/big fight in terms of attention and setup... but then there's a whole extra volume of random bonus chapters.
Anyway, I enjoyed it and it had some grear moments, but definitely felt like something of a flawed work.