About those reserver arrow spells, in my experience, only the Arrowsplit and Bloodfreeze Arrow have any noticiable use. (While Bloodfreeze DC is buggy for my character.)
Anyhow, rangers do create one of the better thrower builds actually. They got free shield proficiency too and you can wield a shield while you throw axes and darts, not to mention that their spell book gets +4 Dexterity, +4 Deflection, and +5 Natural Armor, all of which free item slots for something else.
Anyhow, let us have a look at what kind of damage a Ranger 21/Stormlord 9 can do with mundane throwing axes:
1d6 (Mundane Throwing Axe)
+ 10 (Strength modifier)
+ 5 (Favored Enemies)
+ 2d6 (Bane of Enemies)
+ 1d8 (Sonic)
+ 1d8 (Electric)
= 34.5~ (Damage per avarage hit) Oh, and you can double it with Manyshot.
Then let us consider some Epic Stack of Throwing Axes, maybe the one with +4 EB and +1d6 Fire Damage. The avarage damage for a single hit just rose to 42~... This damage per hit means that the Troll Claw Trolls do not even get the chance to approach you.
As for stats, all you need is a high strength score and 14 in both dexterity and wisdom. You can make do with less wisdom, but I prefer spell casting without that '+ wisdom item' requirement.
And rangers get a ton of skill points, thus you can actually afford to have a low intelligence ability score. You get Heal as a class skill, in addition the stealth and detection skills, oh and you also get Set Trap.
Thus let us have a look at the AC:
10 (Base)
+ 6 (Mithral Chain Mail)
+ 4 (Dexterity with Cat's Grace Spell)
+ 5 (Skin of Cactus or Barkskin Spell)
+ 4 (Halo of Sand Spell)
+ 4 (Armor Bracers)
+ 4 (Dodge Boots)
+ 6 (+4 Heavy Shield)
+ 1 (Cross-class Tumble investment)
= 44
(Luck of Heroes is potential +1 AC, the custom Ranger feat is another +1 AC, and Armor Skin is yet another +1 AC, and you do have feats to spare. And UMD gives a little bit more AC.)
As for additional notes on the Ranger Spell Book:
You got Aid that grants +1 AB, you got Hawk Eye that grants +1 AB, and 'Bless Bow' for another +1 Ranged AB.
Oh and you can easily switch to using a spear if you ever run out of Throwing Axes.
And you get all the ranged feats for free, which means you really got some feats to spare.
Oh, and Rangers also get Non-detection and Polymorph Self, which actually opens up some interesting role-playing opportunities.
EDit:
If you want, I can put together a build with your chosen race. Single class thrower Rangers are nice too, since they really get to get some use out of their animal companion. Actually, I had a Zen Archery based axe thrower before Brutal Throw feat got in, or the other Ranger buffs. In other words, ranged Rangers are nasty. They are the reason why the troll claw trolls used to have silly stuff like deflect arrows.
