Noah Niedzolkowski said:

The way how in the prequels they added way too many new planets, many of which were similar to the original trilogy's planets (for example: Geonosis is pretty much exactly the same as Tatooine), and seemed to forget about most of the planets from the original trilogy. For example: we never see or hear of Bespin, Yavin, Endor, Dantooine, Hoth, Dagobah and many others in the prequels

Um first, this is an EU thread.

Second, there's an entire galaxy out there, why keep revisiting the same planets over and over again. It's a vast waste of potential. It also would have made zero sense to revisit most of those planets as:

Yavin IV - secret base
Endor - secret base
Dantooine - abandoned secret base
Hoth - secret base
Dagobah - secret hideout (which is featured in a ROTS deleted scene.)