I don't think you get extra turns with high wits. You will only be first in the initiative rotation. You can however, get two turns back to back if you delay your turn.
Personally I think it's much easier to buy two +10% crit wands (no need for savescumming) and then use spells with Savage Sortilage to crit. A human with Hothead, high Wits and flame runes already has a decent chance to crit without having to invest points into suboptimal choices like weapon skills. And you can increase that with gear adding to crit chance. Raising scoundrel after investing 2-3 points in any school you need would be a priority, most definitely.
The problem with weapon skills that their scaling is additive not multiplicative like that of warfare or elemental school damage. (You can easily test that by playing around with the stats a bit in front of the speccing mirror.) So it's best to avoid them as long as you have better things to do with your skill points. On a caster I would neglect weapon skills altogether, it's more beneficial to max one or two elemental schools plus scoundrel and maybe respec before certain fights.
