The author of Antonov's Diamonds (most recently queried here) requests feedback on this new version:
Dear Evil Editor,
Former FBI consultant turned pawnbroker Flynn Christopher is asked by an old friend at the bureau to lend his brick and mortar store to run a sting involving fake credit cards. [That's more information than I care to deal with in the first sentence. Dividing the info into two parts with a colon, semicolon or period makes it less overwhelming.
Former FBI consultant Flynn Christopher is asked by a friend at the Bureau for a favor: let the FBI use Flynn's pawn shop for a sting operation involving fake credit cards.]
Their target is Alexei Antonov, an ex-Russian Colonel gone rogue. [Somehow when I read the phrase "ex-Russian Colonel gone rogue," I imagine him running a paramilitary operation, not a credit card scam.] [Possibly calling him a former Russian colonel would be better, as "ex-Russian makes us wonder what nationality he is now.] [In any case, that sentence belongs at the end of the first paragraph.] It should be a simple operation, but instead Antonov has something much bigger and deadlier on the horizon [in mind? in the works?]. At the meet and greet Antonov tells Flynn he plans to takeover [take over] a mine deep in the Ural mountain wilderness and steal millions in diamonds. [When the FBI asks to use your store for a sting, wouldn't they insert their own personnel into the store instead of giving you a major role?] The kicker is, he wants to use Flynn’s connection to the over five thousand members of the American Pawnbrokers Association to fence the stolen goods. [It still sounds like we're talking about stealing uncut diamonds fresh out of the mine. I don't see why pawnbrokers would be interested in that, nor am I convinced that many pawnbrokers would know who would be interested in that.] He leaves out that he is going to double cross and murder his partners in Russia. Flynn is in over his head when the FBI uses him as the bait to draw out Antonov and recover the stolen diamonds. [Still not clear why the FBI cares about diamonds stolen from a Ural Mountains mine. Is there a bigger threat to America than the possibility Antonov will make money selling stolen goods here?] The operation falls apart when Antonov decides he can’t trust Flynn and he has to die too.
Does Antonov have any scheme involving credit cards, and if not, why does the FBI think he does?
You got rid of Peter the Great, but other than that, this sounds pretty similar to the previous incarnation. The plot elements you're choosing to include are inspiring questions. You can leave out those elements or answer those questions.