The balance changes that were made possibly did more harm in the long run but gave Epic a good idea of where things needed to be in Chapter 3 and beyond.
Note - Avoid XP Glitches
When a new Fortnite Season comes around, it's not unusual for XP glitches to pop up but don't give in to temptation! Epic has a history of punishing players who use XP glitches and exploits and it's not worth the risk!
Epic won't take action if an XP glitch affects your account but only if you are seen to be abusing it for long term gain.
Explore the Island!
The easiest way to earn super fast XP early in Fortnite Chapter 3 is to explore the island. As you dissipate the fog of war that will cover the island, you'll receive XP every time you discover a new POI or landmark.
With at least 2,000 XP per location, once you've uncovered the entire island, there are more than a few tiers worth of XP to be had. With each new season, POIs will change and need to be re-discovered leaving more XP up for grabs.
It appears that NPC punchcards are not returning in Fortnite Chapter 3 (yet) so we're back to weekly quests instead. Each quest will be worth 25,000 XP and pretty much all quests are marked on the main and mini maps now.
There are also daily quests that reset each day at 15:00 GMT / 10:00 EST / 07:00 PST. There are also benchmarks for completing a certain amount of daily quests that offer boosted XP.
We're only joking! Kinda... There's a lot of XP to be earned from having a good match with plenty of eliminations and hopefully, a Victory Royale! In Chapter 3, entering a match on the back of a win will also grant boosted XP rewards so getting streaky with your performances will pay off!
Beyond just eliminations and wins, you can also earn XP from foraging/scavenging. This means that being nice and efficient in your looting can also earn you a decent amount of XP when built up over a session of play.
Also, there's the possibility of earning a Victory Crown in each game mode which will boost the XP you earn for as long as you can hold onto it!
This means that if the Battle Royale scene starts to get a little repetitive for you, a break in play won't see you dropping your progression.