FIG Model Drivers Help

Hello Fellow Monkeys,

So here is the deal. I had an interview yesterday for an ER position for the FIG groups at bulge bracket bank think (JPM, GS,UBS, CS). The position is specifically for mid-tier banks. Overall the interview went relatively smooth with the team in regards to fit and general technical questions. However, the MD of the group requested a sample model and a writing sample. I could've sent him the APPL case study in which I learned Financial Modeling and be done with it, but me wanting to earn my marks with my possible future boss I agreed to it. I have started to construct the 3-statement model, but I am currently stuck in regards on the growth drivers I know that balance Sheet would drive the growth, but does that mean that Increase in Deposits= Loan growth and with that Loan growth how do you go above estimating provisions for credit losses and also estimating other types of interest income generation such as purchase of marketable securities, Resale agreements, Interest bearing cash deposits with other banks?

If any FIG bankers/ ER Analyst could provide some guidance and a sample model. I would appreciate.

Thanks in advance!!