I think you may grow to regret selling your klickies. Thirty to fifty klickies is a nice number for an army. As others have suggested, try limiting your collection to only a few favorite themes. This is what I have done primarily due to space considerations. (Storing lots of buildings and ships takes a lot of room and large numbers of klickies and parts take up space too.)
Regarding army size, while huge armies like Giorginetto's look very impressive, they're expensive to create, bulky to store, and time consuming to set up and move. My largest army is my Romans which consists of around 500 klickies. While I'm glad to have them and would never sell them, it's a lot of effort to set them up and move them. I've found that I can have just as much fun, and maybe more, with a few dozen men as I can with a few hundred.
Regardless of an army's size, I like to break it down into units with officers. Generally speaking, I've decided on around 20 men for a unit. I've found this to be a good number because it looks fairly substantial but is easy to set up and move. (It just so happens that I've got 20+ Roman units, which is honestly too many. My British redcoat army of 2 units is much more manageable.) Some of my knight units (lances) have as few as three men and, when combined with other lances, are perfectly fine.
