Well, I know more about my bro, Isamu, so I'm biased here. Yes, I said bro.
I also think it makes things more interesting with the guy we know from way back.
At the moment, Daisetsu seems a bit like a random NPC who won't necessarily live long. Happens in anime plenty of times.
Introduce new character who seems enthusiastic about his job then bam! Dead.
Only time will tell if I warm up to the guy. With how formal he is, I can see he needs a buddy to show him the fun side of life.