Classic glass cannon, but speed and suitability - lacking.
I wouldn't use the exact build in that screenshot, because the mobility does suck pretty bad, but it's less needed on a Ranger anyway. My Rogue is sitting at 11.9m (I think the game rounds up, not down, so it would be 12m).
Thread is about mages
It is, but it's still good to highlight what the other classes are capable of, when Mages can't do this. Well, I keep saying "Mages", but specifically elemental damage based casters.
The real path to power with a "Mage" is Summoner 10 (while using bows + FIN until about half way through Act 2, then respec to INT and spells) > Element 10+ > dumping the rest into a mix of Scoundrel/Huntsman and as high of a critical hit chance you can get. A group of four of those would be a close second, if not tied with a group of four Rangers for a while, and also have an easier time through most of Tactician.
Trying to focus on elemental damage
first is just asking for a masochistic playthrough.
Warfare IS the elemental damage for physical. The formula puts warfare in the exact same spot as the elemental damage for your mage.
The problem isn't that warfare is over powered. The problem is that people aren't taking high ground and putting points in Huntsman.
Warfare is multiplicative, Huntsman is additive. Warfare is factually better in every regard for physical builds.
Fairly sure Warfare, Huntsman and Scoundrel are all multiplicative. It's the Weapon Masteries that are additive. Of those three however, Warfare capping first is always the best option.