Wow, thank you so much! These are some great ideas and critiques, we really appreciate it and we'll definitely be referencing this as we work out the next tasks to-do :)
In the original concept sketches, we actually had drawers on the front side of the desk (bottom of the screen) for storing packages, but putting them above the desk would definitely be a better fit both visually and mechanically.
I could see the "lock" button concept visually indicated with push pins holding the item in question down. Currently you can't lock an item in place, but holding L-shift will preserve the current layering of any held object, and holding L-CTRL will push the held object to the furthest layer. That should solve the map layering issue for now!
The 75-cent stamp was only intended to spawn until the player finds/uses it, so that's definitely a bug that it keeps re-appearing every day. I really like the idea of adding it to the roster of stamps available for purchase, or that using it unlocks a different special stamp collection/pack.
You make a good point about not hiding the forecasted route from the player, potentially it could be a one time upgrade (i.e. a calendar or a marine radio). Maybe there could be a Forecast II upgrade where the player additionally gets more info for the week like you mentioned (i.e. "the Yellow route will only be available on Friday this week"). Love the idea of coloured markers as a tool for the player to mark parcels. We've had the art for wooden handled rubber stamps and ink pads done for about...oh geez, almost a year now...but the implementation had a bunch of kinks to work out with the behaviour/mouse-controls and accounting for all the edge-cases depending on what the player would choose to stamp.
I'm so down for small decorative awards for milestones, maybe the starter pack could evolve visually as different milestones are met. After all this testing, I feel like I have the same 13 images burned into my retinas xD
In terms stamps disappearing, the inconsistency of the unused starter stamp pack's postage all disappearing at the end of the day while the purchasable stamp pack's postage remains, doesn't sit well with us. We'll have to workshop this more in the future, as like you said, if they don't refresh at the end of the day, the player would end up with way too many stamps. For now, we'll probably adjust the balance of the stamps you get in the starter pack (more little denominations) and tweak the spawning rules, which should make it a little easier to have the correct amount of postage on hand.
The shop is not well balanced, items should probably be gate-kept, we threw it together as a last minute addition and it definitely needs some love. Same thing with the routes, but we definitely intend to expand on everything: more complex/dynamic rules, more unique shipping options, more parcel variety, NPCs, quests, etc...
...and we also have a bunch of bigger picture ideas we'd love to implement that we think would definitely round out the game. Thanks again for your lovely comment, it means a lot to us that someone took the time to give us such detailed feedback! Glad you enjoyed playing