The problem that I face with these lockboxes, which is a problem that I believe many people share, is that lockboxes are such a huge waste of money. Spending 750 energy per box, (about 53k today) along with maybe the cost of the lockbox being around 4-30k depending on the box, and most regularly getting an item worth at most 10k is a terrible money sink. It is not really the high chance of getting bad items that bugs me, but the just terribly low chances to get good items that makes it so terrible as a hobby.
A good change does not have to be overhauling the boxes, but simply boosting the chances of getting a decent and rare items. Honestly, if that was the only thing that happened, such that, say, within 5-6 boxes you could easily get something like vertical vents, and not changing anything else would make this not a piece of dead content anymore.
I love doing this kind of thing. Opening lockboxes with a chance of getting something super rare like a twilight aura has always been a dream of mine. Going into college soon, I plan to make it a hobby to farm and open these boxes, and hopefully get something good one day like a wolver tail or an aura. But I really wish that I would not have to go through some hours to get the necessary 750e and the box, just to get something legitimately terrible and a huge loss of money like a plume or a maid headband. This would also help the economy more than hurt it, as most items such as long feathers, vents, and wolver tails are usually at a consistent price and demand.
Here are just a couple of small things that I think would definitely help a ton with bringing back lockboxes as a legitimate idea for possible big money, but not too ridiculous as too crash the economy. I will use the Copper Lockbox as an example as right now Copper Lockboxes are the best lockbox in-game.
1) Give a boost to the percent chance to get actually good accessories, such as long feathers and flowers, along with lowering the percent chance to get low profit items such as maid headbands, plumes, and binoculars. It does not have to be a significant percent-decrease of the bad items, but enough that a good boost (not 1% or something tiny like that) of the better items' chance will allow a more consistent profit to be made off of them.
2) Lower the cost of Silver Keys to around 500-ish energy, such that any player with a few hours can get a key, instead of a 5-hour grind as it is right now.
3) Stagger good items with the bad items such that the chances are more evenly balanced out. Instead of having one or two good items on a higher probability tier, make it more along the lines of 4-6 items.
Just 2 suggestions for now, but they are the best I can think of. Leave other suggestions below if you want, and maybe, just maybe, GH will hear us once again.