Re: Can you secure a sidechain with it's main chain? EDIT: Ardor does this.

I dont want to use or clone Ardor, I was just showing them as an example that its possible to secure a side chain from the main chain. I actually want to side chain Stellar.

To sum it up, it depends 100% on the main chain technology, and if it can implement this.

You can create a side chain of ANY coin, if you plan to provide the nodes & hashing power to maintain it.

If you want to transfer that burden to the main chain, there needs to be some way for you to tell the main chain nodes to validate your sidechain transactions, and mine the blocks that contain these transactions for you.
Not every coin has the technology for this, and if it does, you need to figure out how to achieve it (like ardors centralised way to broadcast your child chain to the nodes).

Do you (or anyone else) think that that would be a good solution? I thought of ways to do that but would it be easier just to clone our own, completely independent chain and then just figure out great incentives for nodes? Also does merge mining require a 2 way peg?

I don't think I can answer any of those 2 questions, they all depend on the type of project you want to launch. For the last question, merge mining just needs for your coin to have the same algorithm as the 2nd coin. There is some work involved in making the miners try to find a solution for both your pow problem and the 2nd coin's, but you don't necessarily need to peg your coin's value to it.