Deleting a giveaway that didn't start should be deleted immediately without removing a slot

They are not counting against your limit, you get one slot removed for each deleted giveaway. Abuse protection.

If you delete 1 giveaway, your limit -1.

Create a support ticket asking for more giveaways slots. If you say to support how many you need, they can help you.

When you push create button, you lose 1 slot and received it back only after feedback confirmed. For each 3 positive feedbacks you gain addition slot. If you just delete GA you can't receive slot back.

You can delete GAs on your own if there is no winner, without contacting support. It will remove a slot from you though just so you're aware.

If they are invite only just don't share them anywhere and you won't need to delete them.

Actually, I think this idea has some merit.

This seems reasonable. If the giveaway hasn't even started yet, nobody's wasted any points entering it or anything. As long as people don't get the creation points until the giveaway actually opens, there's no way to abuse it that I can think of.

yes, it makes sense.

fair suggestion imo.
though i certainly no longer have this issue even if i were to delete hundreds

I too could delete giveaways and not be affected by it. Essentially, those that are generous will naturally build up large number of available slots. At this point, I am able if I so desire, to create 525 GAs.

Losing GA slots only really hurts when one starts out.