Congrats on your decision.
Packing a bike is not easy. Each airline seems to have their own policy. Check out yours.
Also, whatever system you decide on, consider the recovery. I usually use an old cardboard bike box from a retailer. If I have to leave it at the airport, not much is lost. These days not every airport offers to store or hold luggage for security reasons.
Buying an expensive bike bag means that you will have to go from the airport to a destination where you can store your bag until your return and it also means you have to do a round trip, that is starting from and returning to the same location.
Let me know how it goes.