A little of both. The spawn rate is a bit high for all of them, but the wavers in particular tend to flood caves, and coupled with how much health they have, it becomes a nuisance.
As a side note, it feels really really weird to have Ridley as a common enemy. I assume that's going to change at some point in the future, but it's still really bizarre to see the tiny Ridley floating around, and then suicide in lava. At this point I'm just considering them as failed clones that escaped some lab, and aren't quite smart enough to live.
Actually, if you keep them in, and rename them 'Rodney' and maybe a slight recolor, it'd be even funnier. Have them eventually drop the supplies to summon the real Ridley