I would not be surprised to see STEEM drop lower.
IMHO, the decision to buy STEEM POWER should be driven by what people want to do with their account. I think that this is a great time for accounts in the plankton to buy up enough STEEM POWER so that their upvotes are over a penny. I think it costs $160 to get over a penny.
I concur, however,that I would not buy STEEM as an investment ... only as a tool to get more out of an account.