One of the great things about Destiny is the flexiblity in play styles. You can do what you want pretty much whenever and with whomever you want. Beware though. Rushing around like a loon without any focus will cause you to do some annoying stuff later.
The first and foremost of these things is resource collecting. You might not think that Spinmetal you’ve seen lying around the Cosodrome is worth picking up right now but when you realize you need up to eighty of them to get your post level twenty weapon upgraded. How many weapons do you use? I personally have four in common use. The same goes for all the locations. There is always a local resource that you WILL need at some point for upgrades. Get them whilst you are exploring and you save time in the long run. More importantly it gives you time to savour the environment rather than just sprinting from one mission to the next. I must stop doing that.
There is another point to this. Reputation. Below level twenty you can only gain Vanguard and Crucible reputation. By far the most efficient way to increase your reputation with a faction is to complete bounty missions. Each bounty has a clear requirement. Something like collect 200 sensor mites from the Cosmodrome. That means kill stuff in that zone and when you are done we’ll give you some experience points and some Vanguard reputation. The Crucible ones are often something like kill twenty five hunters in the Crucible.
Why bother with reputation though? Drop rates for legendary equipment are deliberately low. Often when they do drop they are not for a weapon you like using. That can get frustrating fast. Once you reach level two in a faction you will be able to buy legendary armour and at level three some weapons. Believe me this has been very handy. As I still haven’t had enough drops to load my character out completely. The icing on the cake though is that there is a tiny chance of getting a yellow bounty. These are a little more involved, a lot more fun to get and result in an exotic item.
I haven’t mentioned Vanguard and Crucible marks yet. Where glimmer is the currency for most vendors for reputation based vendors you need to spend marks. I’ll use Crucible marks as an example because I’ve made more use of them. I love playing Crucible matches but early on realized I could get extra benefit from completing bounties as I did them. I am currently level three and have bought two pieces of armour and a shotgun using the Crucible marks I gain every time I complete a match. You can only gain one hundred marks per server week (Tuesday is the reset day I think). This prevents players from farming these marks all the time and leads to a more balanced play style.
All of the information above will only really pay dividends once you reach level twenty but it will really be worth it. That isn’t the end though. What do you do when your Crucible reputation hits level three and there is little point raising it anymore? You buy a class item from the Dead Orbit, Future War Cult or New Monarchy faction vendor of course. With this equipped all your Vanguard and Crucible reputation goes to the specific faction. These factions can only be joined at level twenty and are a great way to get up to level two in a faction fairly quickly using both PvE and PvP bounties. These vendors have their own legendary equipment for you to purchase with Crucible marks.
The final point I’ll mention is that raising a faction level to three produced a legendary engram reward for me.