I Love Miner's Life. Here are suggestions: More Area's, more sprite diversity, not fully changing blue or yellow when activating the sprite in the shop, random events like avalaches and eruptions that reward the player for not dying, a health bar, obstacles that require certian items from the shop, more towns, an upgrade system for your house and pickaxe, more towns with diverse shops and new ores
I have that code. I'm currently playing your game called Cave Island. Maybe you can make a sequel with 4 islands plus the original to reunite the Dhiamond with a ancient contraption.
The story is that your character is a knight whoose battalion is fighting a beast of unimaginable darkness. The other knights are being thrown around by the beast. You take a daring strike by sliding and slashing him with your sword. The Kingdom then tasks you to avenge the other knights by hunting the beast and it's apprentices. The Beast is then revealed at the end to be a corrupted prince.