Skills and skill groups

My idea for implementing the use of skills is to first make groups; reasonable differing magic and skills to start with. Beyond that there should be damage skills, special skills, damage magic, healing magic and special magic. Shoot (as in with ranged weapons) and steal will be two other specials generally as specific as attack. Maybe there should be shoot skills as well. Damage skills can basically use the same method as normal attack, as in compare with heroic from WOW, absolute value added to weapon damage, attack twice but first with main hand and second with off hand, this will require certain changes to the attack method but I think it will be manageable.

• Attack skills – Use current attack method with different effects, example dual swing, first attack with main hand then immediately attack with off hand (need to somehow implement attacks for offhand), or normal attack with added absolute or multiple value.
• Defense skills – Manipulate defensive skills like temporarily increase block rate to a very high amount or set higher defense and counter probability. Configuration files can contain information such as number of strikes, multiples and absolute values.
• Shoot skills – For later implementation.
• Thieving skills – For later implementation.
• Special skills – For much later implementation, but will probably need to be specifically implemented for every skill.
• Damage magic – Create a method such as that or attack but with functions concerning magic and resistance instead. Different magic use this method with special attributes much like attack skills can use the current attack method.
• Healing magic – Create a method such as that or attack but with functions concerning magic and resistance used on friendly targets instead. Different magic use this method with special attributes much like attack skills can use the current attack method.
• Special Magic – For much later implementation, but will probably need to be specifically implemented for every skill.
  
  I really need suggestions and help with skills, consider the groups.