I do paper scrapbooking as well as hybrid and project life etc. I have a scraprack for my flat embellishments, it might be a little more than you need, but you will be able to see tons at a glance. There are all different sized pockets in each page style. (amazon sells the scraprack cheaper than their site but I wanted you to see the system and she has tons of videos)
http://thescraprack.easystorecreator.com/ Also if this is overkill for the amount of stuff you have you could always just buy the pages and the spinders if you wanted and store these on a shelf. They also sell a storage bag that holds 2 spinders in it. I think it comes with pages too. I have both the scraprack and the travel binder and they are both really good for seeing what you have.
Another less expensive way is to use project life pocket page protectors in either 12 x12 or 8 1/2 x 11 sized. You could print each kit preview and put that in a regular page protector and then follow it with the pocket pages behind it. There are several different sized pockets if you needed larger pockets and of course also regular full sheet page protectors if you print pages too. The down side is if you aren't careful or you overload the pockets stuff will slide out from time to time. (If that happens people put stuff in ziplock bags first but I find that time consuming to deal with ziplock bags).
And another thought, Michaels sells these photo cases that have several 4x6 boxes inside a big suitcase style box. Not sure how much you have or if you like sifting thru cases in one big shot but that would be kind of like what you are doing but with a bigger box per kit:
http://www.michaels.com/iris-photo-b....html#start=20