Skill - stats fighter

[Vallaha]

Well I'M currently lvl 9 and I'm a little bit confused
I spare from now my skill empower ( I have 3 so far of 4)
I want to know if i shoudl empower my slice and dice skills and if the empower switch to the second skill (at lvl 13), the other slice and dice, the skill points I've put on it will switch to the other skill or I have to wait to empower the ''better version'' of SnD? Second, Should I empower my SnD (i'm a 1h sword fighter) or is there a better skill i get in higher lvl, because if i have a better skill I should spare my skill points till there, and if not why?
And for my stats, is it okay to put my spr +25 and just goes for dexterity and strenght after that? I read that end doesn't really matter till my natural stats increase it fast and I'll have alot of hp anyway.
Thank you for the answer I hope I was clear (i'm a french from quebec) so sry for all the mistakes i've done.