Neural network model for sparse multi-class classifier on Tensorflow
The model seems fine to me. Did you try to optimize the hyperparameters? You could use trial and error methods for optimiring the parameters such as,


Learning rate
Number of epochs
Batch size etc,.


And instead of vanilla gradient descent optimizer, you could try other optimizers such as Adagrad, Adam or RMSProp etc,.

Best,
Sangathamilan Ravichandran.