The problem with Necro Archers is the need for all 3 stats- Dex, Int, and Str. One thing you can do about this is take up another form of healing rather than Bandages. I suggest you use Curse Weapon and Spirit Speak to heal rather than use Bandages. If you have a nice balanced bow then you could also use potions. The problem with Bandages is that you'll want really high Dex for faster bandages, but you can't really afford it with the need for Int.

Maybe if you used less Dex and just complemented your slow Bandage timer with well timed Curse Weapons and Spirit Speaks then you wouldn't have to have such high Dex. Not really sure, this is something that you might want to play around on Test with before you decide on.