My suggestion on this thread is going to be directly based on items and how you transfer items from one person to the other etc.
1) My first suggestion: Put the progress bar beneath ore you're smelting below the actual item so you can actually see where it is precisely. This is what it currently looks like:
2) Second: I'm not sure if this is a bug or whatever but sometimes when you're gathering items whether it be forestry, logging, smelting etc the items don't stack in your inventory automatically. Please fix this:
3) Maybe add tiles in your inventory sort of like other MMOs instead of having to move items by clicking on them OR put a minimum box (sort of like a hitbox for your inventory items) to click on instead of having to click on them directly which can be a pain when you're handling branches and tedious items, attempting to drag them but then accidentally dragging your whole inventory across the screen and then attempting to stack your items several more times.
4) Remove the safety(?) drop system where you drop an item and there's a limit on how long other people have to wait until they can loot it. The amount of times this has been an annoyance whilst playing due to me attempting to assist my friend in shifting logs or when I'm in need of food I have to wait two minutes or my friend has to drop another item and then put it into the bag for me to loot it. It's again, tedious and annoying please remove the system. I doubt it'd do more good than harm anyway considering the system is probably intact to stop stealing (correct me if I'm wrong, just assuming).