Suggesting Middlesex don't have much batting past their openers isn't suggesting that other teams have more than two quality bats
They just have this alarming tendency this season to collapse in a heap once Robson/Rogers get out. Even in the chase of 470, Rogers and Robson made over 300 of those runs.
I reckon Rossington is quite a decent prospect tbh. My criticism is more a case of "why are these guys seen as County Championship favourites when they'll probably lose one of their two performing batsmen to England duty, and the rest of their bats don't seem to step up very often."
Warwickshire bat deep but bat mediocre; so, so reliant upon the all-rounders (Woakes, Barker and, seemingly, Jeets + the rest of the tail) to get them to competitive totals; Javid is a decent prospect and Evans might be proving himself to be decent quality, but there really isn't much there either. On name alone, there's no way Middlesex should be going down by an innings to them; the batsmen, Rogers/Robson aside, have underperformed.
I don't understand the point you're making though - you're saying that Denly and Dexter are "very average" along with the rest of the side - which is basically the exact same thing I'm saying!