Ledge is the best act 1 zone. It is easy and there are usually a few big packs to aoe down. I use topaz rings when I do it so I can kill the boss also, but I have no experience of grinding it in a group. The problem with act 1 is that the other zones are all worse than the ledge. The coves had a lot of monsters but you have to deal with tar and vulnerability.
Suicide mobs give xp when they blow up. The western forest has good mob density and is fairly safe (use ruby rings). The problem with fellshrine for melee is that the monsters move slow so you can only kill a few at a time. The reason I would replace western with felshrine in merciless is that western is hard when you first hit merci, so you need to keep charges up to be safe. Felshrine is much easier.
Thi is useless info now, but back in the 9.7 patch Coves and Felshrine were awesome, but they both got nerfed so we are now left with ledge and western forest for fast xp.
Suicide mobs give xp when they blow up. The western forest has good mob density and is fairly safe (use ruby rings). The problem with fellshrine for melee is that the monsters move slow so you can only kill a few at a time. The reason I would replace western with felshrine in merciless is that western is hard when you first hit merci, so you need to keep charges up to be safe. Felshrine is much easier.
Thi is useless info now, but back in the 9.7 patch Coves and Felshrine were awesome, but they both got nerfed so we are now left with ledge and western forest for fast xp.