I did one character a week. Focus on getting your main character up as high as possible. Exotics, powerful engrams and once you hit 280, focus on getting mods to add them plus 5's to all your gear. Also buy some 270 armor for your second and third character from Xur. Save your faction tokens for your next characters. When you start your second and third character, use fire team medallions to help you level up faster. Get through the story and hit level 20. Once level 20, transfer your high guns from your alternate characters and equip the one exotics you got from Xur. Use all of your tokens you saved on factions to get gear that will ascend your level. After that, complete your powerful engram milestones with your new character and you should be damn close to the same light level as your main. My titan was like 301 when I started my hunter. This is what I did and the day I hit level 20 with my hunter, following this method, I went from 187 light to 299.