In light of the new info, I've done my first theory-crafted character! Keep in mind this is based on the assumption that you have to progress on the skill trees; in other words, taking an ability unlocks all of the abilities adjacent to the one purchased, which means you can loop around in interesting ways on some trees. Also, I'm basing this on the assumption that the Arcane/Fade energy blades the KE can summon are a toggle on/off ability that doesn't deplete mana, and you can still cast spells while they (or it if it's just a single sword) are toggled on. This is an optimal melee Knight Enchanter based on the skill info we've seen thus far.:
Spirit - 6 pts
Barrier +1; keep it up as much as possible
Guardian Spirit for +3 Con and 100% barrier when below 25% health, 60 sec cooldown
Mind Blast +1; this will be our Eldritch detonator ability and with the upgrade it also gives us some barrier per enemy hit
Strength of Spirits for +50% barrier bonus
Winter - 6 pts
Fade Step +1; our closing and escape option
Winter Stillness for +3 WP, +50% mana regen when standing still, and spell cooldown reduction when standing still...Arcane Warriors don't run away
Ice Mine +1; use this to keep the closest enemy frozen as often as possible because of the next passive
Ice Armor for +3WP and +50% dmg reduction (!!!) when standing near frozen enemy or persistent cold spell
Storm - 6 pts
Chain Lightning; no upgrade because we won't be using it, just an unfortunate pre-req
Stormbringer for +3 Magic and a 300% weapon dmg lightning strike to an enemy within 25m every 15 sec
Gathering Storm for +3 WP and 0.5 sec spell cooldown reduction per basic attack; we'll be using our magic swords a lot!
Static Cage +1; keeps the enemies close to us to protect our ranged companions and so we can tear them apart
Static Charge for +3 Con and enemies are shocked for 100% weap dmg and paralyzed for 6 sec when they attack while we're casting a spell
Knight Enchanter - 6 to 11 pts (the rest!) also I'm just guessing on the color since we haven't seen this tree
Arcane/Fade Blades +1; this will be our main attack
Active #2; for protection/defense based on the KE description?
Active #3; ditto
Passives #1-4; hopefully they'll be good!
Focus Ability; either Haste or Group Heal I suppose
Use this badboy with a tank (tag team it and stay together!), a ranged DPS rogue, and another Mage unleashing the full Winter tree (to help our Ice Armor passive ability!) and other nukes for some fun times.