If items are going to be involved in the next release, I would suggest also a shop, from where non-essential items can be bought. To buy items, then some kind of a money system would be required. To get money(also experience, skills or what ever), perhaps add some side quests or jobs also in the game. Clients, who hire you for jobs are neutral NPCs (shouldn't be related to the main story). I have few ideas how to earn money:
1) Bounty hunting.
Scenery: I suggest hideout cave, castle, deserted village.
Target: criminals and such
Enemys: guards(I suggest humanoids). Perhaps even put a mini-boss at the end.
Reward: money, items, experience or all above.
2) Treasure searching.
Scenery: mainly outdoors(beach, forest etc)
Target: It could be absolutely anything(chests, rare animal eggs, or what ever is concidered valuable)
Enemys: none humanoid creatures and beasts(wolves, tentacles or what ever strikes the fancy)
Reward: treasure itself or money, items, experience for the treasure.
3) Prostitution.
Scenery: brothels, streets
Target: Horny payer
Enemys: -
Reward: money and/or experience