Any build can be bot, all you need is decent gear and bot settings.
Cast dot (decayed or poison) as your first attack and second attack (talking about isrobot settings) followed by the first nuke.
3rd and so on, should look like this.
AOE nuke, stun, trap, sleep, mag attack debuff, AOE dot
Normal mobs should be dead after the dot + nuke
champs are dead after dot, nuke and aoe nuke
giants and pt mobs need rest of the list.
As long as you grind in non agro mob areas you should be able to easily kill green or white mobs while botting.
To xmedeia
or sub bard

for few reasons.
- while grinding you got speed and noise
- at pvp you will be amazed what the combination of debuffs and the most annoying skill ever (sleep) can do with bard nukes

- its cheaper with sp
- you can leach hp, should be enough to keep you alive combined with vigors grains/hp grains
- lot warlock skills give you time to repot (stun, dull, sleep)
but personally i would take cleric as sub since it is more useful in more situation anyway