And no, there aren't massive swathes of potential avenues of attack. There are only the pathways that bacteria don't share with humans where the drug has no other toxic effect. There will be new antibiotics - no question - but its questionable whether there will ever be another sulphonamide or penicillin.
Actually, GP, had the right etymology - in Italian it would be scenari - but he did blatantly make up a plural that is not used in English. Hypercorrectness is a fault, not a virtue. It confuses your audience and leads them to doubt your accuracy. Kinda silly, really.