Pathfinder is a special explorer, like Cannoneer or Dual Blade.
As such, they have their own character creation, but are still classified as "Explorers". The only restriction KMS introduced was that Pathfinders were not available for open job advancement for a short while (to prevent users from switching high-level/highly-funded bowmen over to the new class without any effort in playing the class).
There is a very small handful of secret areas and interactive objects. For example, you can actually use the outhouse in Korean Folk Town. Nothing to the extent of other games, however.
There are numerous explicit and implicit references to pop culture, including a straight-out Thanks, Obama meme in FriendStory and spoof characters of Bowser and Anna in Mushroom Kingdom. The characters in Kerning Tower are all named after gemstones and the entirety of Omega Sector is a spoof of Power Rangers.
All character classes have unique dialog in certain storylines. Specifically: Black Heaven and Tenebris. For example, in the Labyrinth of Suffering, the voice telling your character not to give up is different for each character:
Resistance characters have Vita
Explorers have Sugar
And so on
Full Metal Alchemist: A long time ago, there was a set of equips in-game modeled after Edward and Alphonse
Naruto: As above, there was a set of equips modeled after Team 7 (or at least Naruto and Sakura)
Bleach(?): There is a set of equips in the game files from a long time ago modeled after Renji and Rukia. I can't actually recall if this made it to GMS, however.
Mabinogi: A small event where you could obtain a Nao chair. Mabinogi likewise has Maplestory events
Sword Art Online: The first official crossover event, featuring the SAO dungeon and equips modeled after Kirito, Asuna, Heathcliff, etc.
Attack on Titan: Several minigames and the battle against the Colossal Titan, as well as outfits/chairs.
Re:Zero: A set of daily quests, outfits modeled after characters, and medals
Card Captor Sakura: Daily quests, chairs, outfits, and medals
Evangelion: Dailies, chairs, outfits, minigames
JMS has had the following events:
SAO, AOT, Re:Zero, CCS, Evangelion as mentioned above
Vocaloid: A set of rhythm minigames, chairs, and outfits modeled after the various Vocaloids
Pop Team Epic: Outfits and chairs modeled after Pipimi and Popuko
I screenshot most dialog and for Lachelein I have something like 600 still images of cutscenes and dialog. When I get home I can pull them up and supply you with whatever you need.
Also, KMS recent added Practice Mode to many bosses which allow users to try the mechanics without wasting a run. I’m unaware of the specific HP values for this mode, however.
Looking things over, Steam has a few problems with Venezuela. I can't find anything about Maplestory blocking Venezuela either. I would double-check with Steam and see if they're doing anything.
End-game is primarily bosses and training. After level 200, you'll move to the Arcane River area, which has bosses like Lucid and Will, as well as the Tenebris area with Verus Hilla, and finally the Black Mage fight.
Bera and NA Reboot are the most popular servers. Most people hang out in towns if they're not grinding or some such.
Choose a class you enjoy playing, not one that ranks high on the DPS charts. DPS charts are flawed, and don't matter any if you're not having fun playing.
