My initial feeling is that I expected more from Gon & Killua or conversely less from the ants. But then again, looking at it more analytically, this must have been a lieutenant class ant and I reckon we saw its full power already. We didn't see Gon and Killue fight at 100%, though. They just didn't feel the pressure or weren't fired up enough at this point. However, the ant dude was already defeated and would have died if not saved by Captain Dutiful. Based on this my earlier prediction wasn't entirely correct as the captains could already be a major obstacle for Gon & Killua, not only the royal guards.

The ant society is falling apart nicely internally, in any case. That much was to be expected when the ants started to show so human characteristics. Maybe that's the reason why the whole world isn't dominated by that species, apart from starving to death after having consumed all food, since they seem to be incapable of anything beyond aggressive hunting & gathering.