Extraction - A heist & bank robbing game

I have had this concept for a while of a heist game with a realistic tone and approach.
You play as a hacker who infiltrates corporations and companies to extract secrets for his own agenda.
But this won’t be a press “x” to god-mode hacking game. It will be based loosely on real-life hacking mechanics.
It won’t also be a “drill and gun” like game.
But involves more of a build up where you extract secrets from targets and piece together your score and give you more options on how you will approach.
So you can rob banks, stores, or whatever in the game.

Here is a WIP made with brushes of a jewelry store in a day.

Just getting a feel on the size and layout of the store.
Next I will close the doors to do some lightening tests
Then material tests later before going into 3d max to do some modeling.

I’m fairly new to UE4 and 3d modeling as a whole, though i have alot of experience in software engineering and c#/c++ programming.
I tried UDK for a couple months and was lost. I was able to learn 3d max on the other hand.
Just days after get the engine this week i already learned more than i did with months trying to fiddle with UDK and a hundred tutorials that confused me more than help.
Its safe to say that UE4 and Epic makes things easy.

My target end results for the store.
http://www.3dhousedownload.com/wp-content/uploads/2012/11/Jewelry-shop-3d.jpg

basic lightening tests.
02db80fbd73e8511da555a908b93238e0d30bd67.jpeg

I think I will stop work on the store and move towards the safehouse.
As I do some materiel tests and modeling in 3d max.
Because that’s where the game will start. And the player would be guided through a series of tutorials that teaches them the games mechanics.
Will keep your updated.

]
basic gaming questions:
third person-first person?
linear;open world;open world+linear?
timeline(2000s,2020s;)?
architectural style(contemporary,art deco,constructionism,etc)?
storytelling style(intro-complication-climax;complication-intro-climax)?