» Sun May 20, 2012 12:14 am
I was working on a mechanic to replace the mini-game in Oblivion with something that combined Morrowind's options (Intimidate, Taunt, Bribe + several others I added) with Skyrim's context-sensitive persuasion options. I can tell you: it's not easy to create a robust, realistic system.
The problem with a system that only uses context-sensitive persuasion options is that it doesn't allow you to inject your character's personality into the game world in a robust way. In my system, you could go around and intimidate every NPC and if you were successful, they would start to fear you. It didn't have to be quest-related. It just allowed you to interact differently with any and all NPCs. If they feared you enough, they would react differently: they would respond with different dialogue, give you information, etc. Some of them would actually avoid you. I was working on mechanics that would allow you to take things from them (mugging), or 'convince' them not to report crimes. You could also taunt people into attacking you, disguise yourself as a member of a faction, etc. There is tremendous RP potential in a robust Speechcraft system.
There were also context-sensitive mechanics, like lying, which was always context sensitive, and some mechanics that were sometimes context sensitive and sometimes not, like bribing or appealing to an NPC's sense of justice. A good system needs both context-sensitive mechanics, and mechanics that allow the player to impose themselves on the world 'just because'.
All of my Speechcraft tests were % based and determined by a variety of factors. It was easier, for example, to intimidate an NPC if you had a high Strength, and you were wearing high-quality weapons and armor. It was easier to Taunt someone if you had a high Intelligence (the primary determinants were still your Personality and Speechcraft). I would never implement a flat, skill-based mechanic (ie. you only get the option if your skill is high enough) for two reasons: first, because it's not realistic, any character should be able to attempt any action, regardless of their chance of succees, and two, because it makes it much more difficult to train a skill. If you can only improve by using a skill and you start with a low skill that never gives you an option to use it, how do you get better? In reality, the converse relationship is probably more true: when your skill is low, it is relatively easy to improve it; when it is high, it should be fairly difficult to make it better. With flat Speech test mechanics you have to implement a system that works opposite to the way it actually does.
Edit: Incidentally, I've earned far more levels in Speech in Skyrim by completing 'convince so-and-so to do such-and-such' quests than through selling gear. Completeing one of these tests almost always earns you close to a full level, and there are a fair number of them. You need to sell hundreds of pounds of loot to earn a level through merchants.