Hi! I’ve had a large gauge septum for around 6 years now & I’m wanting to switch it up. & I have a few questions

1, how many rings would I be able to fit into a 2g septum? (Please include gauge if can)
2, can I put the rings through a tunnel & achieve the same effect?
3, if no to above, say in the future I wanted to put my big ring back in.. would that be possible or would the hole change too much?
4, is stacking solely for stretching? I don’t want to go any bigger I don’t think. I just think stacks look nice.

Thank you xx