Guild Wars 2

It would make all merchant-dependant currencies account-wide, letting us truly enjoy the character we’d love to play at the moment.

Gold is account-wide. Gold gathered with two of my toons can be freely used to buy something for my third toon. Cool stuff.
Laurels are account-wide. I can do dailies with warrior, but then buy something for guardian. Freedom!
Gems are account-wide. No other way to do it, true, but still – a currency.
Dungeon tokens and fractal relics are account-wide. Again, i can choose any of my characters and just do stuff, then move the rewards to another character.
Badges of Honor are account-wide. We also had a developer say that WvW blueprints will become account wide (when asked if it’s fine to drop and trade blueprints with other people), but it’s just a matter of time.

It’s all really great, as it focuses on the player and not the pixel character in the game.

Hence suggestion:
Make skillpoints and karma account-wide, for the needs of in-game merchants, traders and so on; make them account-wide as a currency.

Skillpoints are primarily used to buy skills, and in that manner they should be kept character-bound. But once you have all skills unlocked, they become a currency to be used with Miyani; a currency that represents your general time investment, via the experience you got on your character. Prioritising the player, as with other forms of currency, we should be allowed to use the general pool of ‘account skillpoints’ for trading purposes with Miyani.
50 skillpoints for a mystic weapon – cool idea, but the current system hurts those who play multiple characters, even if they spend more time in-game and get more xp in general, as they need to get those 50 sp on one specific toon. Same goes for 200 sp for a Bloodstone Shard. In the end, it’s the player who crafts a legendary weapon, and the player’s general investment should count, not only with a particular character.

It would require a redesign of the current sp system, to somehow organise the skillpoints-for-skill and skillpoints-for-merchants split.
I suggest to show the character’s ‘personal’ sp to use for skills where they are now, in the Hero panel, and ‘total’ account sp to use for merchants in inventory, by karma.

Karma…
It really shares the story outlined above – prioritising the player, as with achievements and pretty much everything else in the game, karma should be account-wide. After all, it shouldn’t matter much if i’ve done 100 events on a mesmer or a necromancer; that’s a hundred of good deeds done by me for Tyria.
Also, it’s not like karma rewards are somehow overpowered – it’s mostly used for Obsidian Shards (already account-wide), exotic equipment from Orr (which is on par with other exotic gear from anywhere else) and the Orrian Boxes.
Given karma is nothing more but a currency, as opposed to skillpoints, it should be very easy to make it account-wide, with no needs for splits on the way, as it serves only one purpose.

A good idea, in part.

Skill point account wided. No. Its not currency, its used to buy skills to an specific class and only for that class. and you don´t even have to go to a merchant to do this. Even with the Myani thing you will have to get every skill. If you make this account it will be easier to make new chars, just use the wasted skills points from other char to get the better skills.

Karma account wided. Yes. You can use your karma to buy gears that will be used for every char in merchants, and you now have all those liquid karma that you can put on bank and use with every char.

Skill point account wided. No. Its not currency, its used to buy skills to an specific class and only for that class. and you don´t even have to go to a merchant to do this. Even with the Myani thing you will have to get every skill. If you make this account it will be easier to make new chars, just use the wasted skills points from other char to get the better skills.

You haven’t understood my suggestion.
Keep sp, as used for skills, character-bound. Make sp, as used at Miyani, account-wide.
200sp for a Bloodstone Shard is quite a lot, and i don’t see the point of having to grind those sp on one toon if i have all 8 professions and play them all; feels i’m being punished for going for diversity, so promoted elsewhere.

So you want two SP systems (yeah it will have to be like this), one account wide when you buy something on Myani and other char based when buying skills.

When you buy something they have to sum all SP from all your chars and… How many points it will take from every char? What if you need to spend some points in a skill but buyin your bloodstone you spend all of them and then another has a lot?

It´s not viable. From logic point of view.

The only way to make this work is making something like GW1. You trade your SP for an item, this item is account bound and when you have sufficient items you get them with one char and then you trade it for something.