The unfortunate thing about Voyager is that most episodes are filler. Some of them are quite good filler, but very rarely will you see anything important happen.
The problem with "Persistence of Vision" is that it's not good filler. It's dull and nonsensical. A good filler episode would usually get a 5 or 6 from me, and on the rare occasion a 7 or higher. DS9 had a lot of filler episodes in the first few seasons, and even some in the later seasons during the Dominion War. Despite being filler, a lot of these episodes managed to be really entertaining and/or interesting. Some of my favorites included "Whispers" and "Little Green Men."