[KMST] [1.2.375] Monster Park

The problem is, the entire game is designed around the pot spamming system. Most classes do not have HP recovery skills - I count only 7 out of 18 classes that can reach level 200, and only one of them is capable of healing other classes.

Recount.
Currently in GMS:
Battlemage - Blood Drain
Mechanic - Healing Robot H-LX
Aran - Combo Drain
Bishop - Heal
Bucc - Energy Drain
NL - Drain
Shadower - Chakra
Paladin - HP Recovery
Dark Knight - Dragon Wisdom/Aura of the Beholder
That's 9.

Post-Chaos:
Dual Blade - Vital Steal
Making 10.

Post-Class Balancing (so far):
Hero - Self Recovery
Dark Knight - Beholder's Revenge.
Making 11 while giving one class their third recovery skill.

The fact that they insist on adding recovery skills shows that they have at least a little drive to eliminate pot reliance. Granted, there are still issues such as the fact that, even among the classes that get HP recovery, there are issues of when they get it.

Nexon decided a long time ago that bosses like Zakum weren't challenging enough when everything they could throw at you could be dealt with by not lagging and carrying enough pots, but instead of fixing the system for the better they started designing HORRIBLE things like Damage Reflect, mass Seduce, and Dispel spam, none of which are fun or challenging to deal with, but just a huge pain that requires impossibly fast reaction times or a lot of NX. The game has gotten further and further away from being fixable and Big Bang wasn't nearly enough to change that.

I'll agree that their methods thus far have been misguided, but that doesn't mean the game is getting further away from being fixable. Nexon is just kind of stupid. We know that.

While you point to things like Damage Reflect and Seduce as awful game mechanics, I'd say that the absolute worst skill they ever gave a boss was the first: the ability to 1/1.
This was the step Maplestory ever made towards "fake hard". Instead of coming up with a pot cool down system that would force players to think about when and where to recover HP/MP, they stuck in a skill that would ensure anyone would die if they didn't pot immediately.

Yet even this travesty can be mended; just take it out.
They could do the same with any other "fake hard" aspect of bossing without a major overhaul.

They'd have to redo the entire HP system so that levels matter more. HP gain should be exponential instead of linear. Warriors shouldn't have 7-8x times more HP than Mages, and 3x more HP than Archers. HP Washing shouldn't be possible (or necessary). MP needs to be a limited resource for all classes - otherwise that just leads to unlimited heals, which means heal spamming, which is boring. They need to give ALL classes a limited means of recovery, enough to train and fight easy bosses, or solo play will be a nightmare. Passive regen, like you said, would be nice. Then they'd need to redesign most endgame bosses to be less "cheap." No insta-kill damage reflect, thanks. Then they'd need to entirely redesign the Bishop class and throw some healing skills out to a couple of other classes. Only then could they actually make pot cooldowns work and healing be useful.

Is HP washing isn't necessary since Big Bang hit? While HP and MP (and defense) probably could still be adjusted, I don't believe they need to be. Mages don't need as much HP because they have Magic Guard which means that only 20% of the damage they take affects their HP anyway. Keep in mind that pot delay would affect MP pots as well.

It'd take a lot of testing and adjusting, but I'm confident that pot-reliance could be eliminated purely by allowing every class to either recover some HP or just avoid taking damage. For example, while the archer class doesn't have any recovery skills, they do get a skill that allows them to dodge at a 20% rate.

Of course, like you said, bosses would still have to lose their "fake hard" attributes, but that's something for which I've been hoping for a long time. The only reason they have them in the first place is, as you said, because of the horrible pot system. "Fake hard" is the effect, not the cause.

Healing doesn't have to be boring AoE heal spam, either. I play a Restoration Shaman in WoW, which is a healing spec of a hybrid class, and it's actually a ton of fun. I have an AoE placer that heals everyone by a small amount per tick, a one-target buff that heals the target by a decent amount every couple of seconds when they get hit, a small but cheap heal, an expensive burst heal, and a chain heal (works like Chain Lightning). I also have some other buffs and passives that affect my healing ability. Having limited mana means I actually have to choose my skills carefully. My gear improves the amount I heal, the speed at which I heal, and my mana recovery. I'm not asking to see all that in MS, but that's the kind of depth I want to see in a game. I enjoy playing support classes and I want healing to matter, but there's just way too much they need to change. Might as well make MapleStory 2.

First of all, despite rumors, I don't see a "Maplestory 2" ever happening. Maplestory is a game that relies on players continuing the characters they already have, and Nexon would be alienating their consumers by making everyone start over.

Most of what you suggested is actually possible in the current MS anyway. The only one that wouldn't work would be one-target buffs (since there's no current interface to choose a specific party member to cast on).
An AoE placer already exists (Healing Robot H-LX).
Not sure what a "burst heal" is, but it sounds like an AoE.
Chain Lightning and Sparks already demonstrate chain-targeting, which could be adjusted to player characters.
MP Recovery gear already exists via Potential.
Int could easily be made to determine how much a skill heals.

A final note that I want to add is that I believe that the penalty for dying in Maplestory is too harsh.
Having to get back to where you were is punishment enough. If you're training, you can lose your map.
If you're bossing, you don't finish the run and lose out on exp/items.

Simply by getting rid of the exp loss would open up doors in this game. Players could actually explore and experiment with training instead of being punished for walking outside the lines.