Massively has a great interview with Neverwinter's Andy Velasquez where he takes time for some retrospective evaluation of the game and controversial subjects including lockboxes. In addition, Velasquez speaks about the Foundry and what players might expect in Module 2.
Our discussion turned to the "necessary evil" (as we posited) of lockboxes. Velasquez admitted that lockbox keys are top sellers, although he put a big asterisk by that when he observed that what the players are really buying is the chance for a rare mount or companion. The value of those mounts and companions is backed up by the straight-up sale of such items in the store.
So, are lockboxes necessary in the free-to-play model these days? "Yes and no," Velasquez said. "They're not a universal truth."
Ultimately, the studio wants lockboxes to have appropriate perceived value so that players don't feel bad spending money to open them -- and don't feel bad avoiding them altogether.
Read the full interview at the link above.