You can make your cards and then send the off in Marjorie's Potpourri. It runs every month, no set theme, and you only send 5 cards. Very easy way to move along cards (ie, leftovers, duplicates, or new creations).

When creating a tracker there are choices: Singleton, Swap, Other
Sounds like you are describing a "singleton" rather than a "swap."

"A singleton is a single LTC card that the tracker owner has available for distribution. Only the tracker's owner can add cards to the tracker."

There is also another option:
"No subtype is the wild, wild west of LTC trackers. It's not a singleton nor a swap, which are the most common organizations, but what it is is anyone's guess. There may be strange and unusual rules involved, so read the description of the tracker closely to see if it's someone you want to get involved with. Anyone can add their own boxes to such a tracker."

Might consider the postage cost too of sending your cards and whether you will expect receivers to send a SASE.

How many cards are usually in your sets?

depends on how much supplies I have for the card in mind :P

Thanks for the info!