Always remember to speak with your programmer!
In our game, some 3D was kicked out because it doesn't fitted the proportions in Unity project. For example walls and floor.
Our artist developed a full set but it arrived too late! :(
Remember to ask your programmer (or Unity project manager) about sizes, proportions and navigation of AI. Also how are the props programmed and animated. So you don't work in a prop that he cannot use later!
¡Always learning in game jams!
Our game look great anyway!! :D:D