Some suggestions:
1. You could always just eliminate the charisma statistic. You'd have to move some of the skills and powers around to other stats, but you'd eliminate the "dump" stat.
2. You could change some stats. For example, you could eliminate Wisdom and Charisma in their current form and add Perception and Willpower. Spot, Listen, Sense Motive, and possibly even ranged combat modifiers could come from Perception, while Divine and Sorcerous magic could be based on Willpower.
3. Ignore it. If the players are happy with their characters, it may be more trouble than its worth to force the issue.
4. Change the focus of your adventures. If your PC's spend all their time banging down doors and playing "pin the longsword on the Orc" then the role of Charisma on gameplay will obviously be lessened. Introduce more political and social aspects to your game.
5. Change the expectations of the stat. You said that all the stats except for Charisma have obvious effects, but I disagree with that. Charisma very obviously and directly effects the outcomes of all social interactions. Just make it clear that while players may earn a small bonus (+2 at max) for good roleplaying to a roll, the main thing to consider will be the stat and skill ranks.
1. You could always just eliminate the charisma statistic. You'd have to move some of the skills and powers around to other stats, but you'd eliminate the "dump" stat.
2. You could change some stats. For example, you could eliminate Wisdom and Charisma in their current form and add Perception and Willpower. Spot, Listen, Sense Motive, and possibly even ranged combat modifiers could come from Perception, while Divine and Sorcerous magic could be based on Willpower.
3. Ignore it. If the players are happy with their characters, it may be more trouble than its worth to force the issue.
4. Change the focus of your adventures. If your PC's spend all their time banging down doors and playing "pin the longsword on the Orc" then the role of Charisma on gameplay will obviously be lessened. Introduce more political and social aspects to your game.
5. Change the expectations of the stat. You said that all the stats except for Charisma have obvious effects, but I disagree with that. Charisma very obviously and directly effects the outcomes of all social interactions. Just make it clear that while players may earn a small bonus (+2 at max) for good roleplaying to a roll, the main thing to consider will be the stat and skill ranks.
