Certainly. That's why I've placed my prequel efforts on the backburner. I have another thread in this sub-forum about a prequel trilogy that features a post-Sith conversion but pre-black armor Darth Vader as its protagonist, but I find that very difficult to write about for the reasons you mentioned.

Ultimately I think the key to writing effective Star Wars prequels is to let go of the idea that they have to be 100% about Anakin Skywalker's fall and the conclusion of the Clone Wars. I'm sure the pre-OT era can be made more interesting than a simple retread of the familiar and soulless Lucas material we saw in his prequel films. If you can get creative enough, there's plenty of room to mine for interesting story ideas.

I might as well scrap even my Vader prequel trilogy idea, now that I think about it.

I've turned to writing a sequel trilogy because the ending is not set in stone, especially since I'm not conforming to the established post-ROTJ EU timeline. There are some elements present in my sequels that will be recognizable for EU fans, but they are dealt with differently than you might expect. Right now I won't say much more than that. Down that path lies spoilers!