When choosing a plan consider the medical maximum and determine if it is enough for where you are traveling. Health costs in the US are very high, but are generally lower in other countries. For example, when travelers are required to purchase insurance for European countries, they only require $50,000 maximum, so this should be sufficient.
On the other hand, you may want to make sure you have a high amount set aside for Emergency Medical Evacuation particularly if you will be in remote locations. Also be sure that if you plan on adventure activities, that your plan will cover injury/accident related to that. Even downhill skiing may require a special sports rider to be sure it is covered.
In today’s uncertain world, some people would like to cancel for reasons beyond the “allowed” reasons for most policies. This option will cost you more, but consider the importance to your peace of mind and the protection of your investment before you decide against it.
For example, most policies will allow you to cancel if there has been a terror attack where you are going, but perhaps not if it was merely nearby. Same will be true for natural disasters. This option would allow you more leeway in your vacation plans.
Other items of importance may be luggage loss amounts, rental car coverage, etc. Some of these are available as riders to the basic policy and some are set in each policy.
Exact amounts of coverage vary by company, so be sure you check all the details that may be important to you. More companies are offering coverage for lost electronics/cameras which may be important depending on your trip purpose.