I do like perch, I have eaten many pieces of fried battered perch that were very very good. I have not had any in quite some time though. I have eaten some very tasty rainbows and brook trout in the last few years. I try to avoid recently stocked fish but there are many two year hold over rainbows in my home river and a self propagating population of brookies upstream that are very good eating. I don't often harvest fish though. I would rather let them grow and catch them again most of the time.
With that said I have had good and bad tasting fish of most species. I have had carp that tasted better than some trout I've eaten, I find that fish can be highly variable in how it tastes depending on the environment it is caught in so this is a very difficult question.
My absolute favorite fish is atlantic cod fish and chips.
On the topic of white sucker. There is lots of white suckers and fall fish in the Connecticut River and I have heard that in the spring when the water is still below 55 degrees they both can be really good eating. A very nice flaky white meat is what I am told but as the water warms up it starts to take on a off putting flavor.