Yes

If you want to start a new character, you may, but it’s important that you do not keep decks built for characters you’re not actively playing — doing so would use up cards that you should be encountering during play. If you switch characters for some reason, it’s best to write down the cards in the previous character’s deck (or use the free character sheets posted online at paizo.com/pacg) and return the cards to the vault until you want to play that character again.