Like I said earlier, someone that determined to level is probably less concerned with RPing. The idea is not to force people to RP but to help out those who already wish to do so.
You may not be able to
force people by such mechanics, but you can give them a little push, that might have a strong long-term effect. I would certainly be helped into roleplay by such pushes, and I am quite sure not to be alone.
Besides the already suggested mechanics to completely avoid people to be able to mine, cast, smith and kill at the same time, you could just make it extremely difficult in comparison to being able to do just one of these jobs.
Mechanics, that could do that, were skill costs that rise with the PP, that were already spent (instead of a cap).
Another option would be a maximum rate of PP, that can be spent per day (RL day to prevent ressource wasting AFKers). This might be combined with unspent PP decaying over RL time to prevent players from rotating characters.
All the suggestions about limiting the number of crafts, etc. could be modified in such a way, that you can get quite far in every job, but can only excel in one or few, so to create an item of extraordinary quality it needs more than one player.
A lot being said about levelling, I will throw in some general ideas, for the details of which I have no idea yet, but someone else might have:
- For completness's sake and knowing well, that this is a real challenge: What would really improve RP is a realistic PvP-System, that is able to prevent mindless player killing.
- The non-violate conflicts could also use some support, since they cannot be felt: The races get along fine with each other, there seem to be no big political debates, only the religions seem to squabble a bit. Of course there needs to be some background for a good debate, which would be a task for Settings, but I think, Game Mechanics could provide something too.
- What about guild houses? On one side, I have not yet been inside one, so I might not be that qualified for this topic. On the other hand there is a reason, why I haven't: As far as I understood it, a guild can open the house or parts of it to the public for sales, games, recruitment, advertising, etc. However there is no way to find those open houses without checking all of them (I want big flashing neon signs, telling me, that they are open). So this is something, that could be improved.
- There could be help to people playing merchants: Different buying and selling prices in different locations, that change over time; big carts, that can be used to carry around huge amounts of stuff, but cannot be disbanded and inhibit from anything but moving and trading.