I have a D&D 3.5 group of four players, the classes are; Wizard, Rogue, Barbarian, and Swashbuckler, the level of the players is 4. (Having no healer is part of the game, not part of my question)
My question is about the Barbarian and the Swashbuckler. They are both melee combat characters, and both fill the same role in the group. The problem is that the Barbarian is just so much better at combat than the Swashbuckler, causing the player playing the Swashbuckler to feel inadequate and under-powered in comparison, mainly the player has complained about being totally outmatched when dealing damage.
The Barbarian wields a great axe with 18 strength, meaning his damage with two hands is 1D12+6, and 3D12+18 on a critical, not to mention on a power attack he trade in up to 5 attack bonus for twice as much damage normally, and three times as much on a critical - the Barbarian can then deal an average of roughly 20 damage per attack without a critical hit (1D12+6+8). Not to mention that with rage he can deal even more damage, and has more hit-points than the Swashbuckler regardless. The maximum damage that the Barbarian can deal on an attack with a critical and full power attack is 66 (3D12+18+12), while the minimum without a critical and no power attack is 7 (1D12+6).
The Swashbuckler wields a rapier with 12 strength, and 20 Intelligence (racial bonus) meaning his damage is 1D6+6, and 2D6+6 on a critical, his threat range for critical is 18-20 so it happens more often, but not often enough to match the Barbarians damage - the Swashbuckler can deal an average of roughly 9 damage per attack without a critical (1D6+6). The maximum damage that the Swashbuckler can deal on an attack with a critical is 24 (2D6+12), while the minimum without a critical is also 7 (1D6+6).
As you can clearly see, the Swashbuckler is outclassed in damage, where his maximum damage is less than the Barbarians average. Yes - the Swashbuckler has many skills and more flexibility in combat - including more AC... But the player feels totally useless when dealing damage.
Should I introduce some elements to help balance this? Or let the players simply live with the consequence of their choice? If I introduce balancing elements, should they be overt or covert? Or should I do something else entirely, or a balance of the three? In other words - I seek advice on the situation.