Having flown with 4 toddlers at one time, one toddler doesn't seem daunting to me.
Find a toddler sized back pack and fill it with items that would entertain during the flight. Make the toddler wear it and keep track of it. Buckle it on so it's not easily taken off. The backpack will also be easy to grab when the toddler tries to wander off. This way you won't have to add toddlers entertainment stuff to your carry on items. This also gives the toddler some responsibilities and makes them feel like they are a big help on the trip! I would go shopping with the toddler before the trip to pick out their new back pack so it's exciting to them and also to get a new toy, book or something special and not letting them play with it until the plane flight. This will add some extra incentive for behavior as well and give them something to look forward to. Also, a new toy will keep their attention better than an old one. The child might not understand what the trip is about, but they can certainly understand that they have new toys to play with and fun things to do while they are traveling. They can look forward to that.
Put your rig into a carry on backpack. There are backpacks out there that will hold a rig plus extra stuff. This will keep your rigs handles covered and also let you carry it on your back so you have hands free to chase the toddler. This way you can also fit your jumpsuit, and diapers for the toddler into the backpack with your rig. You won’t need a whole diaper bag for one flight. Only carry on what you think you'll need. Borrow a helmet when you get there or put it into checked baggage.
I'd scale back on what you take. When you get there, you can always buy a $10 umbrella stroller for the trip rather than dragging yours along. That seems like more hassle than it's worth. Do you really need a whole diaper bag or just a few diapers for the trip and buy some diapers when you get there? I’d really think about what would be nice to have and what you really NEED. What you can buy there later versus taking what you have at home. You might be surprised at how little you really need to pack.
I would make the toddler walk as much as possible at the airport too. Even though the toddler might slow you down a bit, get there early and allow for this. Ask your toddler to carry things for you and help you so that they feel important and have something to do. Even if it's just a useless piece of paper or something, give them jobs to do. Giving them something to do will help keep them focused somewhat while you are busy with things. Constantly praising good behavior will reap more good behavior. “You’re so good! I don’t know what Mommy would do without you?!”
Choose your battles and realize that a child will not and should not be expected to behave like an adult. I remember one time when my 4 kids were very small. All of them were 5 years old and under at the time. My son was around 2 or 3 at the time and he got a cookie and a glass of sprite from the flight attendant. I was juggling an infant on my lap and the other two girls etc. I looked over at my son, sitting by the window and he had crushed up his cookie and put it into his soda to make a thick paste with it and was finger painting on the wall of the plane. I figured it could be cleaned up later and let him as he was being quiet and entertained for the moment as well as being very creative! The key is not to get to uptight or upset and rattled while traveling or the toddler will too. They take their keys from you. If your toddler is out of control, take a second and reflect. Sometimes you both may need a calm hug.
Traveling with small children doesn't have to be a bad experience if you prepare for it. Enjoy the trip and make it enjoyable for your toddler too! Give them choices as often as possible to make them feel like they are a part of the trip. "Do you want to wear your red shirt or your orange shirt on the plane?" "Do you want to eat your cheerios now while we wait or when you get on the plane?" "Would you like to sit here or over there when we wait for the plane?" "Would you like to stand on this side of me or the other side of me while we wait in line?" Little decisions like that mean a big deal to a toddler and makes them feel in control when things seem out of control to them. Always think of little choices they can be making along the way to keep them engaged. We all have choices. They need to be making their own, no matter how small so they feel like they are doing something and in control of what is going on.
Constantly talking to your toddler about what is going to happen, what is happening, and talking about the tings surrounding them at the time will alleviate a lot of their anxiety. Asking them questions and engaging them in age appropriate little games will help too. “We’re going to the airport! What will we see there?” “How big is the airplane we’ll fly on?”
“Look at the yellow cart? What is it carrying?” “While we wait in line, let’s see if you can stand on one foot?” “Can you stand on Mommy’s feet?” If you constantly engage them, and distract them, the trip will be more enjoyable.
Hope this was a little helpful! Have a great trip!