While I'm all talks before fights, I always have that weird feeling that persuasion is the easy way in in most games. It's often just a matter of choosing the right dialogue option and voila!
This is an issue with cRPGs, they often make dialogues the lazy option. Convincing a dozen guys you're here for business with the press of a few buttons vs having to spend 15 minutes killing them all : in all honesty I can view the killing them all options as the harder hence the more rewarding thing.
What's more, dialogues in cRPGs are often driven by sheer numbers - do you have enough in Charisma ? Do you have enough persuasion ? If you need points specifically allocated into a secondary ability ( ala Fallout ) to convince the guy handling explosives that you know your way around explosives, do you have enough points in said ability ?
In DOS this is further aggravated by the fact you can reach high score of charisma without ever spending points, hence without ever sacrificing precious ability points earned when leveling up into Charisma. Meaning that just because you're wearing the right set of equipement, you can mostly safely win your arguments.
On the other hand of course, you found a way to avoid a mindless bloodbath, so there is that.
Pillars of Eternity is the better example I think of rewarding the player. No XP is gained by killing people or talking your way through : you gain XP when you complete the quest, that's it. How you did it doesn't matter. It obviously implies a real hard level cap as the XP available to the player is clearly pre-defined, and the level the player will reach in the end is only determined by how many secondary quests he did. I can't see that as an issue, if anything it helps balancing the game out ( you know what is the minimum level the characters will be at any stage, and what is the maximum level he can reach )
