To keep some party dynamics alive with role playing elements each player should choose two party member as Links, and choose the type of Link that exists between them. There are both positive and negative types of Links available. The reason for choosing a negative Link is not to create conflict in the party, but to give the character something to work toward rebuilding/over-coming.
These are all Role-playing aids that help players "get into" the role of their Hero. Having a link to members of the party helps them to dismiss the meta-gaming (ignoring the knowledge that player has) and try to play the situation as their Hero would. It may not be the smartest thing in game terms, but it might be much more heroic, or better for story-telling, in the encounter or situation is thought as if it were to be "retold" what might make it more interesting.
Some example Links are:
[+] Promised Protector: an elder Hero, or possibly stronger has promised the others family that they would keep them safe, or do their best to keep them out of trouble. They may take on more dangerous tasks, even if the other volunteers for them, thinking up lame reasons for themselves to perform the task in place of the other.
[+] Teacher/Student: The two heroes have a Teacher/Student relationship, where one is significantly better at a task then the other. This might be even in a Gateway that the other has not even entered yet, but the role-play of the teaching/learning could still be played out.
[+] Family: Maybe a brother/sister or cousin relationship exist, this typically represents the positive side of this types of relationships. In this sense, it is more the assumed complete trust, and good nature toward the other, knowing that the behavior will be reciprocated in the future.
[+] Admirer: This does not have to be in a sexual manner, but simply that one Hero cannot do the things of the other, and they have a fascination with that other Hero's skills. They may go out of their to watch them in battle, or do favors for them when in town.
[+] Similar Interests: The two simply have one or more similar interests and enjoy the company and conversation, when the two are together they may even get a little lost in conversation about their joint interests and may even lose sight of what is going on around them.
[-] Distrust: An inherent distrust of the other party member exists. This could be played blatant initially, but the idea is for the Heroes to work toward patching this up (not on the first adventure together, but over time). This could be conveyed with taking watch with the distrusted Hero, or going with them on a scouting mission, simply to keep an eye on them. Or it could be more secretive, paying others for info on them, or to tail them, or simply observe and report.
[-] Envy: Similar to Admirer, but the underlying intentions are not as pure. There may be a desire to see them fail, or to attempt to show them up, such as if they miss an attack, this Hero may attempt to kill the creature that is on the "Envied" Hero to attempt to draw a complement, to to show them that they can succeed when some better then then fails, thus proving they are better (right?).
[-] Rivalry: Hopefully done is sporting manner, like competing for the most kills in an adventure or battle by battle. Often these are different styles of Heroes, one trying to prove their weapon to Gateway of choice is superior, since they can kill more "baddies" then the other...even if the other does not know there's a competition going on.
[-] Personal Item: This is simply something you believe another party member has that belongs to you. Whether you lost it and they found it, or it was lost gambling and changed hands until it ended up with them, or at least they are the last one that had it. You want to check their things to be sure its not hidden in them, and if not try to ask them where the item was place or sold.
In addition to Party Links, a Hero may want to apply a trait to themselves, or a few that gives them some guiding principles for their Hero. These might be Arrogance and Justice, for a warrior that knows they can get the job done, but continually fights for what is right. Another Hero my go with Knowledge and Generosity, they do what they do to learn more, and they continually give a lot of their treasures away.
Giving your Hero a couple of minor guiding traits can make the easy to play, but even with these it does not require them to act a certain way all the time. If you put Brave down, and some unknown person is asking the them to go into a Troll lair to retrieve an item, they don't have to agree simply because they are brave. Most brave individuals have done so, when they have a hope of surviving...So people can tales of their bravery later.
As a GM I have found it very useful to have players develop a few NPC's that their Hero knows, each with a minor story. Theses can be from the little girl they saved from a goblin named Shawna, and the Hero stops by to visit her and her family when ever they are in town, or their Black smith friend, Molar, who vowed never to make another weapon, despite his superior skill in this area, as his son was killed by a weapon that he was previously commissioned to craft.
These are very easy adventure hooks that a GM attach a story, it might be difficult to get the party to agree on a price to retrieve and item from a group of orcs, and negotiations could break down if handled poorly...but nothing would get the group moving on just such a quest if...While the party is hanging at an inn, Shawna's crying mother comes bursting through the door screaming "There took her!". The Hero connected to Shawna is going to ask little more than "Which direction did the go", and he'll have all those orc's heads lined up in the Bounty Hunters shop...more fun and exciting, less haggling over "how much is it worth to you?", but if the negotiations did occur and they failed, this hook will likely get the party to recover the item, but they will have more negotiation power if they are holding the item in their hands.