Need an opinion for Factions

Hey everyone.

Recently I've gotten back into Guild Wars, and I need to ask for opinions concerning my characters. I am going to buy Factions not too long from now, and currently I have two characters: A level 20 elementalist/mesmer, and a level 12 monk/necromancer (which I am currently working on in the Prophecies campaign). Once I get Factions, should I:

1. Take my level 12 Monk/nec to the Factions campaign, and stop doing the Prophecies campaign (if that's possible).

OR

2. Finish off the Prophecies campaign with my monk, get him to level 20, and then head off to the Factions campaign.

OR

3. Get Factions, abandon my Monk, and start a completely new character in that campaign setting.

Sorry if this questions sound a little newb, it's been a while since I've played the game. Thanks in advance for any comments.

First, start a new Factions character and play it through from the beginning to get the full experience. Worry about bringing others over later.

My opinion only.

Don't delete an old toon or you'll lose your time towards the year mark and the mini-pet. Merging the two campaigns gives you 6 character slots so there's no need to delete any of them.

You don't have to finish before heading for Cantha, you can go back and forth as desired. Still, I'd finish before moving on.