It'd be pretty difficult to find a better archer.
I did an experiment.
I went to Cann in the Shivering Isles (Mania side).
It's a large dungeon, so I felt it would be good for testing.
I took a http://www.uesp.net/wiki/Shivering:Amber_Bow#Amber_Bow. I took 200 http://www.uesp.net/wiki/Shivering:Amber_Weapons#Amber_Arrow, but without an enchantment on them. They're the level 23+ type, but with no damage health. The reason I took non-enchanted arrows is because I have never found a matrix for amber arrows. Even if I did, 25 isn't going to last long. Thus, normal amber arrows.
I fully charged my bow with soul gems. Completely. my bow holds 4150 magic points. It uses 55 every time it fires. A full charge will provide me with 75 shots.
My goal was relatively simple. I wanted to count the number of arrows it took for me to kill each creature as well as counting the number of creatures killed. I also wanted to see how many arrows I generally managed to recover.
I have the best basic bow amber can buy. It's even already enchanted! I am two points shy of the best possible marksmanship skill. I have the best unenchanted arrows in the game.
Here were my results:
I killed 53 creatures. Most were conjurers so they were nice and soft. Everything else was a Hunger - also not particularly tough.
I fired 212 times.
I started with 200 arrows. I ended with 91.
This would indicate a recovery rate of "about half" for the arrows. It came out to be 45%. For the record, I scoured the place for arrows too. The nice thing about amber arrows is that if they are present, you can definitely see them easily. Even so, I only managed a 45% recovery rate.
It cost me slightly more than 4 amber in arrows. However, I only recovered 2 amber from the entire dungeon. This left me at an amber deficit of 2.
It also cost me 11,660 magic points to keep the bow charged. In fact, I ran out of the charge along with several soul gems before I even finished the halfway point of the second area of this dungeon. I had to cut out to return to town, recharge the bow and buy additional soul gems to carry with me into the dungeon in order to complete it. Even after purchasing every soul gem in bliss, I only barely finished the dungeon. This is 8 grand soul gems worth of magic.
When the hunt was over, however, I had only acquired 1 greater, 1 grand, and 3 lesser soul gems. This left me with a magic deficit of 7960 magic points.
I also consumed 5 homemade healing potions in the process - not to mention running around a dungeon like a kitten on PCP because I had to shoot and retreat from the hordes of conjurers that would see me if they were in a pack and I tried to pick one off.
This is a conjurer dungeon. Heretics.
I've also gone into dungeons such as Milchar, which is composed of standard monsters. While the amber yield there is enough to sustain the hunts, it's still somewhat close. I generally wind up with a massive magic point deficit as well. If I run into necros or undead, it gets very ugly very quickly.
It's honestly kind of... This kind of svcks.
The reason I tracked all this, posted all this, and wrote all this isn't just to whine and complain. That's not the point at all, actually, as I long ago gave up the idea of being an "archer type" in Oblivion.
Skyrim is announced for this November though, and my hope among hopes is that Bethesda really, truly discovers that not everyone who plays their game wants to be a sorcerer. Please make that possible in the next one.