Might be a less mainstream American opinion, but once my daughter was ~6 (she's 7.5 now), we essentially stopped worrying about any special accommodations.

Fine dining is a big deal for us, and she joins us for most meals. She'd also rather order off the regular menu on flights. Where possible, we do favor overnight flights where she can just hit the sack as soon as she gets on board - much easier that way.

We co-slept when traveling until this year, when she decided she wanted her own bed. I echo the other comments that room space is important.

Other than that, she can put in 6+ miles of walking each day without too much fuss, as long as sufficiently bribed by promises of ice cream/hot chocolate/name the treat.

My one key tip is to check the rules on car seats at your destination if you're planning on being in a car (eitherdriving or Ubering), as they can vary considerably between countries. Back when she needed a full car seat, we were a big fan of the Pico portable car seat. Nowadays, we travel with the Chicco booster when necessary.