@Zenopo and @Desanthian
You can import your GW1 progress into GW2 on a daily basis, every 24 hours.
So you can either unlock all the characters in GW1 and import them to GW2 and continue to grind away to unlocking the rest, or you can start playing GW2, unlock them all in here and then play GW1 a few times a week for the next year until you reach 313 for Unicorn Chomper.
I would suggest, obviously doing what you want to do, first and foremost but only your characters and abilities from GW1 will transfer, not any customisations or progress. Coins are so much easier to farm in GW2 that I would highly suggest that you play it and unlock everything in this one, if you're deciding between the two.
GW1 is a painful challenge grind, and the more challenges you do, the less skip stars you'll need to skip the ones you don't want to do.