[Edit: By the way, this is a wish list thread. You wish for none of these mistakes to be repeated.]

There should be a main goal in this game that may take years and years to complete.
No.If you want goals to complete, play singleplayer. There is no \"main\" plot in an online game. There never was and there never will be. Diablo is another example of this... boring... gameplay style. Quest, quest, quest, done. New difficulty. Quest, quest, quest, done. This is not what is intended for PlaneShift. There will be multiple major quest plots, full of dead ends and even more trick questions and sub quests, that even if you hunted every day for 10 years, would never be able to complete, with more quests added all the time.
To make it simple, just for you:
Bad styles:
Diablo (complete the game, gain levels and items).
Good styles:
Still non-existant.
SWG has the best economy around in a MMORPG. 100% player driven, no NPC shops.
Have you ever played Project Entropia? Excellent economy system, not because people are able to extract their ingame money to real life money, more because people actually want and value the money they have, rather than throwing it away on something useless. And people actually think before they buy something, which is diffrent to many other MMORPGs where money is worth nothing to people.

Anyway, to get back on topic. A mistake I\'d like to see corrected in PlaneShift is the use of numbers. Numbers in games are bad, as they make people think they can \"win\" the game by getting their number higher than everyone else\'s. As long as there is a number they can compare, they can say \"hah I have 1 more than you so I win\", and that\'s bad. Very bad. No matter what it is. So the fewer numbers there are, the better.
Another mistake I\'d like NOT to see in PlaneShift is the occurance of magic items. You are not to go on a quest, kill monsters and find so many magic items that you have to actually discard some of them. That\'s bad. Very bad. Magic items are rare and their owners should praise them and protect them with their lives, not dump them on the ground for some other Obah Dood Axe of Doom +3.
Mistake number 3. No sane person would put a sword into his/her backpack. Nor an axe, or any other weapon for that matter. Talk about a back pain... A backpack is used to carry supplies, not weapons. Weapons are kept in the person\'s belt or in the person\'s hands, or in a sheathe designed for that kind of weapon. If a person cannot carry the weapon, he/she must drop it and cry about it, or put it somewhere safe and come back later for it.
Mistake number 4. Anything a monster or humanoid NPC drops when killed should be sellable and worth picking up, and dropped items should remain in the game forever, until picked up. Food and other things that rot, should rot after a given time period, such as an ingame week or two ingame weeks, depending on how fast such things would actually rot.
Mistake number 5. In most, if not all, other online games it is not possible to put away your weapon, whenever you wish. People should be able to sheathe their sword or axe, and city guards should enforce this. If you draw your sword on a crowded market place, you\'re asking for trouble.
That\'s about it... For now.