Also, seeing as The Accountant had a very healthy sense of humor about it, Christian’s riffing with/about Jason Bourne would serve as a breath of fresh air for the uber serious Bourne franchise.
Well, first and foremost, it gives Jason Bourne someone of similar training to team up with.
Above all other ideas, an Accountant / Bourne team-up would give us something we’ve needed for quite some time: an on-screen reunion between Ben Affleck and Matt Damon.