Alamy has recently started a subs package deal offering to larger buyers, but not right down to current micro prices. Can't find a link atm, but it seems that that's what three sales I've had in the past week which were zoomed and notified on the same day were (that didn't happen before except Personal Use, there's usually a long waiting time.)
Whether having the same images on micro is harmful is moot. You'll read different experiences about that.
Don't only consider what some people say on the Alamy forum. Many have a hatred for micro, which is fair enough and understandable, but no experience whatsoever of micro. In the Golden Days of micro, some of them would have made far more on micro than they ever did on Alamy, but they refuse to believe that.
I'd say that Alamy is a different market, and traditional micro stuff doesn't do as well there, but that's only going by anecdotal experience I've read, nothing scientific.
I only have exclusive RM images on Alamy and I don't sell much there. What's particularly difficult is working out what sells: for me, it seems totally random.
People I know personally who supply live news do well there; in fact, for two of them, it's their livelihood
A couple of forum regulars do well with very 'pictorial' images.