I chose to do the structural framing using 12x24 timber because of the architectural aesthetics of the building. I thought that it fit better than steel given the existing outer facade / feel of the model. For the beam system, I chose 8x10 timber because it made more sense to have smaller members between the larger members. I made sure to not block the atrium or the stairwell (as can be seen in the image). However, walking through it — I think there might still be some classes with the railing and the columns.
My strategy:
I pretty much first made a grid system based on the existing rooms. I used the architectural view first to see where the rooms where so that I wouldn't be placing a column in the middle of a room. After that, I made sure to remove the members that would stock out in the stairwell and the atrium. I then used the beam system tool to load in smaller members and just selected it so that all of them would be the same orientation. For the sections like the atrium and the stairwell, I put in a standalone beam so that it would create an additional section so that I can place a beam system without covering the original area (that would've covered the stairwell and the atrium).