To any future readers:
I implemented a quick tool to automate memory size estimation based on the approach above.

  
      
      GitHub
  
  
    

jacobkimmel/pytorch_modelsize 1.5k

pytorch_modelsize - Estimates the size of a PyTorch model in memory


  
  
    
    
  
  


As this discussion outlines, note that these size estimations are only theoretical estimates, with implementation details altering the exact model size in practice!
Hope someone finds it useful