Great work!
Might I suggest a sort by category in the inventory screen, similar to how you can sort by battle items, etc. in the crafting screen. If you need to sort by craftables or quest items, for example, this would be useful. Similarly, a category in the market could also be useful (e.g. food, battle, craftables).
Perhaps a basic 'special' attack for the combat, which would allow people to experiment. It would also serve to make the guard option useful instead of redundant. I realise this might be out of your scope, but thought I'd suggest it if you decide to expand in the future.
Looking forward to the updates you have planned with the quests! Would also be interested in the exploration, and ally portion of the battle system, if you feel comfortable with those at some point too.
This will be big help to many, so thank you for providing it to the community!