I just took a Titan to level 20 in just over 6 hours. (Admittedly an alt but he only benefitted from the other characters after level 20). Essentially I used these pointers: Collect every Vanguard and Eris bounty you can complete. (Did not do any crucible but a few or those bounties can be completed in a single match. Like the zone capture one on Control. So those might also be worth a look). Always select a story mission at or below your characters level. (This is to avoid having to repeat sections). Only do missions once as you only get EXP the first time. (Notable exception is the first Moon mission which can be completed again to complete the Eris 5 Special, Hive triple kill and Vanguard 20 Fusion rifle double kill bounties. Also first Mars mission is good for Cabal major / Ultra bounty). Use the Destiny timers app to match a patrol with public events. Pretty much only do patrols when you have a bounty to complete six. (Should be offered these via post master). Note this is likely to mean you will need to do more post level 20 to grind Vanguard reputation. Only do Strikes once you are 2 levels above the advertised level to mitigate against drop outs. (Try and match these with the bounties for killing the bosses).