I think I'm pretty early at switching to heavy with DW in isekai. Here's me clearing the 80-round arena on PFUDOR with DW heavy:

Equipment and stats after:

Not terrific equipment, but it's forged a bit, mostly with self-dropped mats. Club is soulfused because I can't be arsed IWing it 6 times when I can finish it in 3 for a small fee. Between FB insta-killing 4 monsters, sleep, and weaken on whoever's left alive and awake, I have no problem handling rounds with lots of monsters. I have silence fully upgraded too, but I didn't even use it.
Here's me clearing the 65-round arena after:
