So I am asking: What is the spirit of 4e?
First off, you're breaking a lot of the unspoken rules of the system. Level 6 utility granting the ability to glide? Even limited flight is strongly discouraged in the Heroic Tier, and you're just handing it out to this class?
Secondly, classes aren't based around their equipment, neither are their powers. Or ammunition for that matter...except perhaps maybe the Ranger, but it's trivial to carry 3 quivers of arrows. It's not trivial to carry multiple packs of heavy ammo and heavy rig equipment. Have you even done the calculations on whether someone can actually
carry all of this? Since Strength doesn't seem to be a primary attribute, do you realize that like a 12 strength can only carry 120lbs? Armor and shield alone will eat up 1/3 of that...how much does that leave for your equipment?
Lastly, if you're new to 4e and RPG's in general, why are you designing a class? You need to play the game with the existing classes to get a feel for how things work first. Take a look at the Artificer for some ideas on how incorporate "technology" into a class more. You can't just walk into a system and start designing classes because it leads to all sorts of balance issues and such.
Like your level 3 abilities? 1d10+INT+Immobilize versus 2d8+1d8 Fire damage? Assuming an INT mod of +4 you're talking 9.5 average damage (average of 1d10+4) and Immobilize versus a power that does 13.5 average damage, with 4.5 of it being Fire. The problem is, with no INT mod damage on the second power, it doesn't scale at all. So there's no point in taking the second power because the first one becomes stronger over time, while the second one does not. Not to mention the fact that Immobilize (save ends) is worth a LOT more than a measly 4 damage.
As for the "spirit" of 4e, they're probably referring to what "powers" actually represent. When a Wizard casts an encounter or daily, he's using a tremendous amount of magical energy to cast a powerful spell. He can do this once per encounter, or even once per day, because it's such a drain. When a Fighter uses an encounter or daily it's because he momentarily sees an opening to perform a devastating attack, or because he summons all his power into one single strike (like with Brute Strike). These can only be used once per encounter or once per day because they're either Herculian feats of power or because he sees a temporary opening that doesn't show up all the time.
Basically, the power are "cinematic". They're big, loud, impressive and limited. Yours are just arbitrary. Why can you only use a Cannon Spear once per encounter, but you can use a Fire Javelin whenever you want? It's just an arbitrary "this is stronger, so it's an encounter" mechanic. It doesn't represent those "cinematic" moments when a PC goes above and beyond their normal power to accomplish something epic. This is the "spirit" that you're missing.