This is our experience of travelling with 8-month to 11-month old baby (that's how old she was on the return trip). Maybe it will help or at least prepare other first-time parents for their first time trip. Our experience is based on flights with Emirates and Malaysian airlines travelling from Germany to Malaysia and Japan.
Preparations and what to bring
Stroller, carrier and car seat
We bought the lightest and most compact stroller that we could find. It weighed only 6kg and came with a bag with shoulder straps. Once folded and packed it can be carried just like a shoulder bag and is even small enough to fit in the overhead compartments of airplanes. At some flights we could bring in the stroller as a hand luggage, other flight we had to leave to stroller at the door of the airplane and we would get it back after we left the airplane. Normally we should have gotten the stroller back right after leaving the aircraft but a few times we only got it back at the baggage claim. I guess, after folding and putting it in a bag it doesn't look like a stroller anymore. So that handy portability backfired a bit here. But since we also brought a baby carrier it wasn't much of a problem.
Another reason we picked this particular stroller was that it comes with an adapter to mount a car seat on top. This way it was easier to transport the car seat which we decided to bring along. In the end we hardly used the car seat in Malaysia as it was inconvinient to always bring the car seat along for short trips. And as far as I know car seats are not mandatory in Malaysia when taking a baby along on a car. In Japan, however, it is mandatory so we always used it when we took a car ride.
to be continued ...
airplane baby bassinet
the information above states: "Baby bassinet must be stowed during taxi, take off, turbulance and landing" hence on a bumpy flight you won't have much use for the bassinet. Also note the monitor above which is very bright and can't be switched off so we needed to cover the bassinet with a cloth during night flight
pushing the sleeping baby in her stroller while enjoying the view of Nagoya (Japan)
Sleep routines are very hard to keep up if you want to see anything of the places you visit so the little ones will have theirs naps in the stroller in the strangest places. Sight-seeing with a stroller was impressingly convinient in Japan. There is always a subway station nearby with clearly marked elevators and ramps.
the challenge of pushing the stroller in KL (Malaysia)
In contrast to Japan using a stroller in Kuala Lumpur (or any other place in Malaysia) is a challenge to say the least. High sidewalk curbs, missing ramps and elevators or no sidewalks at all, etc. makes it difficult to enjoy walking around the city. It would be more convinient to put her in a baby carrier if it wasn't for the humidity and the heat.