This really depends on how rich you are and what you can trade for. Of course the Wf is nice, but in lower levels I found a Goldstrike to be the bow of choice: good speed and with a Perfect Skull dual leech and very easy to obtain. I don't know if this can be upped or not. Lycander's is good as well for levels under 60 - good mods and can be used at level 42. My BOTD is not nearly as good as the Wf for most work but it is fun to use in a camp of demons in Act One or so.

The bowazon is a tough road to go these days.