Tony,
I l-o-v-e "The Bank Job"! Like you said, one thing going for it is that is based upon real events. Truth is stranger than fiction - and that makes it easier to pitch a seemingly improbable story.
Notice in the opening scene of "The Bank Job", it's established that Terry, the family man, is not squeaky clean. An employee is rolling back the miles on the odometer of a car. And he partners up with Martine, a woman with a shady past and present. There are hints in the conversation between them that he has a shady past and that they were a couple in that past. That is why Martine is now soliciting him for the bank job.
Your logline reads like a plot for a heist genre movie. Therefore, like it or not, these are elements script readers and studio executives expect to see in the script:
+ A big theft. Substantial money or wealth is at stake.
+ It?s never just about the money. It?s about revenge, punishment, vindication.
+ Ergo, the mark has to be at fault for the crime to be justified. It can't be a crime against an innocent.
+ The suspense is whether they get away with it.
+++ The dramatic interest is in the details of HOW the heist is pulled off.
(Notice, I mark the last item with extra pluses. This is the most important element in the genre. The fun and games that sustains the audience's interest is procedural, how they go about the heist.)
As you may have noticed, a focus on a character's personal or family life is not on the list. It's useful when it can be worked in as a "B" story that dovetails into the "A" story (see Ocean's 11) -- but it's not primary to the genre.
And it's import is often revealed as the "A" story unfolds. (For example, though there's a plant in the opening, the big reveal of Danny's Ocean's primary motivation for robbing those 3 particular Vegas casinos doesn't come until 45 minutes into the film. At the point, the audience discovers that the most important stakes for Danny are love; he wants to win back his ex-wife,Tess, from the ruthless casino owner, Terry Benedict.)
Yada-yada. Sorry to bloviate. My takeaway is that like it or not, Hollyweird will pigeonhole your logline into the heist genre. And the above elements are what they WANT to see when they read the script.
Regards and best wishes.