Skill and Stats and implimenting new ones

Ok, lets say that for launch i build my character for maximum effectivness in whatever skill, trade, or role currently avaliable.

Down the road they patch in a new trade, skill, or weapon type, that i now would like to dabble in.

How does character stat decay and stat adjustment really work...

If im clubs now and want to go bows down the road, is it going to be a situation where i have to reroll to avoid months of bow training? Is there a way to adjust your characters abilities natually...for when the rest of the game arrives?

I currently plan on nerfing a few character stats and maximizing one or two, however later on if they add skills related to those nerfed stats i made now, is it going to be worth it to keep my current character....or will i be able to adjust to the new skills without wasting the previous 6-9 months of play.

Just curious...id like to plan for the future somewhat, however if they include something cool down the road...like a spirit stat based, shoulder mounted nuclear grenade launcher...id like to be able to use it effectivly as soon as possible.

Or lets say i decide that crafting is for me...i love to play with my little baskets...but im a combat character...

Or what if willbonney decides he wants to rage on noobs and grief people...how will he be able to adjust his characer for maximum noob greif...or will he need to reroll..

whats the process for switching roles and adjusting stats?