Minimal Attrition - Frank Concept

Here's another character concept for 'Minimal Attrition'.

Although the structure around Minimal Attrition is based upon heists/robberies, I wanted the main story to be very character focused. I'm very interested in dysfunctional families and wanted to incorporate this into the project.

So, I'm exploring a dynamic between Nathan (still not keen on the name...) being forced to work with his father, Frank, to complete the heists.
Frank used to be a bank robber but, due to an armed robbery going wrong, he spent a number of years in prison, leaving a young Nathan and his mother with nothing. Despite Frank trying to reestablish a relationship with Nathan when he got out of prison, Nathan still resents his father and they haven't spoken for years.

This is the base concept I've drafted to help try visualise Frank and to further establish that, even though sci-fi elements will be used in this project, the look and mood would be very 'present day'.