and Odium is Agent Smith?
back to the topic! personal theory: Stormlight is pure power (perhaps a splinter, or sliver of shard-power), most likely a gift from the Almighty by way of his Highstorms, and can be used in a Variety of ways(powers Armor, powers blades? fabriels, raidents, money, good lord, its everywhere!((except shin?)) )
Spren are Magical, Sentient, Emotional and can help a Human use Stormlight, but are not made of it, and might be from the Almighty, Cultivation, or the 3rd Shard(lots of debate possible here, where are they from, what do they do, can you trap them in a Poke-ball?).
And the Glass bead is mostlikely the Goblet, which implies that even rocks, and non-living objects have a Representive in Shardsmere(Shallen tansformed a Goblet into blood, Jashnea turned a Bolder into smoke, and regular soulcasters do all sorts of stuff, trash into metal/food/clothes/etc)
getting to Shardsmere itself might be easier with Stormlight(especially if its acutely shard-power) but since Hoid, and his Hunters(17th shard?) uses it to travel, their must be other Methods(meditation? aeons? willpower? death((one of the visions is a word for word description for it)) )