The channeler understands the natural connectedness of all living beings. His skills reside in bringing to existance these links, and to manipulates them and bends them to his will.
He is a spell-caster who is dependent on his links to cast his spells. These links have to first be established before use, and they create a visible energy link between those characters linked. Link creation can be interrupted, or once a link is established, a character can remove it (as though an enchantment) or by moving away a sufficient distance from the link source (usually the channeler, but occasionally can be linked to other individuals).
Attributes
Links (primary): Points in this increase the duration of links (hence the number of links that can be established), and increase the potency of link-based spells. Most link spells have no effect by themselves. Sample spells: link target ally, link target foe, network (springs random between already-linked characters and new characters), sever link (breaks links, but in the process drains health, gives damage, etc), strengthen links (increase the potency and duration of links), hub (adds static hubs through which links that get broken can pass through instead to reach further), elongation (temporarily increases the distance links can stretch over before they break), hooked link (damages ennemies when a link to them is broken), linked arrow (next arrow damage inflicted from a linked ally adds a link between that ally and the foe that was hit).
Surge: Various damaging / healing / buffing / battery spells (mostly with effects over time) that require links to function. Also includes a couple of "feedback" spells, which require a link to be established between multiple channelers (primary or secondary), and feedback spells co-activated by all channelers included in the feedback link. Also include a few spells to counter other channelers.
Mindmeld: direct spells that temporarily link the channeler with a single target, and produce various effects (damage, drain, etc) as long as the channeler maintains the spell active. That is, once the spell is activated, its effect continues until either: (1) the target moves out of range, (2) the link is broken (interrupted or removed), or (3) the channeler moves, attacks, or uses another skill / spell / etc. Importantly, in all cases, the channeler must interrupt his own spell to cast other spells or move. Many mindmeld spells benefit passively from other active links at the time the spell is cast (e.g. X damage per second, plus 1 for every link active at the time the spell is initiated). Some spells steal aspects of the target (i.e. steal armor while active, drain energy) while others do damage over time.
Heaven and earth: Enchantements that add potency and effects to the links. Only one enhancement can be active at a time. Heaven skills add cold damage, slows ennemies, increase speed of allies, and regenerates energy. Heaven skills however damage the caster over time with lightning damage. Earth skills heals (roots), add earth damage, and knockdowns / daze. Earth skills also considerably reduce movement speed of the channeler.
Balance:
The channeler plays much like other casting classes, with an emphasis on AoE effects (Surge & Heaven and Earth), buffs / debuffs, and includes some direct effects (Mindmeld). Most of these spells either require links to be established before they are cast, or benefit from links to become more effective. As such, channelers are less effective at the beginning of a fight than other casters, and really shine through when they create and maintain multiple links. Because these links are visible, however, opponents can try to break these links via a multitude of methods including killing the channeler (which removes all links he established), isolating a bottleneck in the network and disrupting that link (see above for methods), etc. If players ignore the channeler and take no precaution to remove the links, he will be as effective as other casters that are allowed to add conditions, buff / debuff / etc with nobody impeding their efforts.
Stronger spells are balanced by being similar to spells in other classes, e.g. gale, unstable earth, etc. Even though these spells might be stronger with more established links, they usually will only have an effect on the target.
Why it would be fun:
This class introduces a new dynamic, where players are rewarded for cooperation, either in establishing and maintaining links, in establishing feedback links, or in breaking opponent links. Because the links can be broken with distance and using standard debuff spells, they do not require additional counters. The class is not unbalanced relative to other caster classes, as the links essentially "selects" the recipients of spell effects, thus potentially extending the area of influence (AoE) of those spells at the cost of establishing and maintaining them.
The complexity of creating and maintaining links is not for everyone. As such, some players who are interested in this concept will enjoy playing this class, while other players can skip on the experience. Players playing against this class will need to incorporate some strategy and a minimum of puzzle-solving to be effective in countering this profession.
A

