Senteria: Now I'm thinking of increasing my dex to 15 for 4x melee and then dodge. What do you guys think?
The higher your DX, the higher your speed: which means more attacks you get in turn-based mode, and the faster you attack in real-time.
There are gloves you can buy to boost your DX (or rings you can craft, if you're technologically inclined instead). There are also boots you can buy which increase your speed. Getting your DX all the way to 20 also provides a small bonus.
I might also suggest pumping more points into spells, since the higher your MA, the more devastating the Harm spell becomes. I like Temporal and Conveyance spells (Teleportation becomes THE spell to have from the mid-game on.) but you're more than welcome to mix things up however you like.
Protip: When you get that far, the Melee and Dodge mastery quests are interwoven. Seek out the Dodge master first to unlock the best ending.