I'm not certain about scaling costs either, but presently there isn't any real feeling of impact when choosing your beginning stats. For trying to avoid the concept of dump attributes, I still find myself maxing 3 I really want and spreading the rest as I can. A mild percentage difference just doesn't come across as very meaningful. Dexterity for example tells me I'm getting some flat value to accuracy, but it's really difficult to conceptualize how much of a bonus it really is at different levels.
Probably need some more time using it as well with the confusing aspects of might affecting all damage, etc.