Yeah, I think Vin Diesel doesn't really have that Hitman in him. He's more of a "bang-bang, slaughter-slaughter, mission accomplished" kind of person while they should get a "sneak-sneak, strangle-strangle, silenced bang, mission accomplished" kind of a person.
And I really don't know how you can get a plot for a movie from Hitman. It might just be hard enought that it'll make the movie crash and burn
"Our posturings, our imagined self-importance,
the delusion that we have some privileged position in the universe,
are challenged by this point of pale light.
Our planet is a lonely speck in the great enveloping cosmic dark.
In our obscurity – in all this vastness – there is no hint that help will come from elsewhere to save us from ourselves."
- Carl Sagan