On of the bigger issues is how to stay connected to your loved ones and to the internet.
Depending on the country most of the hotels and Restaurants have WiFi but for instance in Australia it is rarely free and sometimes very expensive. Usually the cheaper the hotel the better the internet and the higher the chance that it is free.
I never tried those worldwide WiFi access spot offers and also not the mobile pre-payed SIMs you can have that work in several countries. In your vacation you do not want to go hunting for hot-spots.
It is also cumbersome to always check and sort the hotels if they have internet.
That is OK if you are staying in just a couple of hotels during your trip. If you are planning to stay in 50+ Hotels this gets tiring. Therefore: stay independent.
This is what I did:
Cost is about 10-30 $/Month.
The difficult part is that the setting for MOBILE DATA is correct. If not: not internet.
How this is done differs completely for each country.
Therefore: do not leave the shop until you are sure you can surf one the internet!
The Good news: Sooner or later it always worked.
If you are just checking your E-Mails, some surfing and some Google-Maps then 300 MBytes/Month should be enough.
Bigger things you do in your Hotel.
What operator you take? I have not clue, usually I just took the first I found. We were always lucky.
You have to check the internet yourself if you are concerned about coverage.
Thailand:
I took the one that is sold in the 7-up stores. Worked well.