Levels 1-3 can be some of the roughest for an adventurer. They're just getting out there and figuring out their abilities. Their whole adventuring career is head of them. And they can be taken out by an ornery housecat. So, instead of trying to create an adventure to run them through, let Gaming Honors do that. The Exodus of Wolfbane is an adventure for characters level 1-3 that's up on Kickstarter now.
From the campaign:
In this original 1st-3rd level adventure, survivors of a brutal massacre must endure the long trek to a mythical refuge called Stonewater. Guided only by an ancient map, and aided by the mysterious powers of an injured spellcaster, your adventurers will confront mountains, monsters, and marauders on their dangerous exodus. Along the way, the heroes might just uncover centuries-old secrets and right ancient wrongs...
...if they can survive.
The campaign's on its way to 2x funded with 11 days to go.