I think the price hikes hurt the Arena sets ultimately... Like the Droid Factory at WM. Though that last round of DF sets were pretty dismal ultimately, and were in short supply for the most part which I think helped them appear to move ok. But the original sets were everywhere and seemed to sell at about the same rate.
The Genosis sets were weird. They were bumped in price, and though they were decent quality, they weren't the steal tehy had been at $9.99. Those Order 66 sets were pretty great, but those hit super steep discounts... They seemed to ship several times over though, so maybe Target just overordered on them when the first rounds went fast?
2-packs have steadily decreased in quality though, and increased in price. Now you get nothing but repacks, and they don't seem to move at all. Those Geonosis Arenas are gonna look like a godsend here in a few years I think.