You need 17 dex after tomes to qualify for manyshot. Without this don't bother with archery.
You need 19 dex after tomes to qualify for improved precise shot. Without this I wouldn't bother with archery (though this is more flexible).
This character concept that you're looking at is one of the hardest to make work that I've tried my hand at. Honestly, if you don't have gear, possibly a past life or two and relevant account options (half-elf and monk) then I wouldn't bother.
In particular, the bar has recently been raised with archery with the change to 10,000 stars enhancement. Due to this change I would no longer make any archer character with less than 6 monk levels. In light of this I wrote up a build
here. This is a rough sketch which has a decent amount of versatility in the details. There is a link in the OP of that thread with some older AA builds which remain viable healers.