Likely you can choose Pre script build (start skills) for each of the main characters you wish to recruit.
Other then that what more do you need? I personally did not feel like one need to maximize the maximum potential of a character to play this game.
But maybe they do? Your fun doesn't have to equal his fun.
Here is a post that can help OP customize the entire party I wrote out for someone else.
If one get happy by one more Attribute of STR to get a 1% dps Improvement I guessing you missing the point why the devs made it a open class type of video game.
You get only a limited amount of points to spend. That is most important for talents.
For example, if you choose Ranger as starting class, you get Arrow Recovery as talent. The next talent point is at level 4. If you like the talent, fine. If you think it is nonsense (like me), you are bound to it nevertheless.
I would like to know wether you will be able to customize. I don't care wether it is at the beginning or after Act 1. If you cannot redeploy all points (talents above all) after Act 1, I would never choose Ranger as starting "class" for my companion ranger, but a different.
Not starting as Ranger as ranger is a bit strange, but better. You see the problem?