As a stand-in, I'd be OK with Origi too. An understudy doesn't have to be as good as the first choice for that position. He does have to be good enough to perform to the required standard when called upon, but (genuine question) how can there be any reasonable doubt after last night that Origi meets that standard?
And sorry, but the "I'm sure there's better out there" argument is a bit of an iffy one without actual names and some idea whether those players would be available at a fee we'd be willing to pay. Example: some scoper on a Facebook page I saw earlier today was saying.we should go after Son. As if.
He also is different from Firmino in style - much more physical, even though Firmino is tough for his size. I think if he plays a little more, he can be a good option against certain teams. And, I expect Brewster is something different too.
I don’t know much about Brewster, but in my mind he is more of an Owen type. Is that far wrong?