Why is there not a space on the entrys for player's current or last ratings? It would make it easy for TD's to make sure everyone is in the right division? Has anyone tried this before?

for the most part, its pretty easy for the TD the way it is now.

Before the event, the TD is emailed a list of all current PDGA members in the area and what divisions they are elidgeable for.

Plus if you put a pre-reg list up online, it lists that players current rating on the pre-reg list. If someone signs up intermediate and has a rating of 920, someone, if not the TD, will notice it and give the heads up.