A question that most people would ask when packing for a vacation is "how much gear should I bring?". If you bring too little, you may fear you'll miss out on a photo opportunity. On the other hand, you would not want to lug 6kg of photo gear during a vacation (that's the amount of gear I carry for 10 hours at a wedding). Over the years, I have tried out many different variations in my quest for lighter loads during a vacation. This is especially crucial when you not only have to carry your camera gear, but a baby and shopping bags as well. All the parents out there will know what I mean.
In the end I have come to the conclusion that all I need for a short trip is a full frame DSLR camera body and a 50mm f1.4 lens. I am selling photos taken with this combination on Shutterstock and Dreamstime. If the photos are good enough for the stock photo libraries, I believe this gear combination should be good enough for most of us.
Outdoor photographs benefit from diffused light during a slightly overcast day, which prevents harsh shadows. If you don't have the benefit of a cloudy sky, try shooting in the evening or early morning, taking note which direction the sun is shining, and make sure your subjects are facing the sun. If you are shooting at mid-day with the hot sun directly above you, find a shady tree and shoot under it.
A simple window light setup, using sheer curtains to diffuse light, can give very nice portraits. A full frame DSLR is preferred, coupled with a 50mm f1.4 lens. You don't even need f1.4 because f1.8 is equally good, and available at a fraction of the price.
A full frame camera is not absolutely necessary, because you can create this shot even with an APS-C (crop factor) DSLR. I just favor full frame for its clean high ISO images, especially if I'm travelling light and do not want to carry a speedlight. Taking photos away from the window light will require you to use a higher ISO setting, but you will still be able to get a decent image, with an acceptable level of noise. Sometimes it's more important to capture the moment than to aim for technical perfection by asking your subject to move closer to the window, allowing you to use a lower ISO for a cleaner image. But you would risk losing the expression of the moment.
If you have an APS-C (crop factor) DSLR, you can achieve a similar field of view as my combination above using a 35mm or 30mm lens. If you are using Nikon, the 35mm lens would give you a 35 x 1.5 = 52.5mm field of view. If you're a Canon user, it would be 35 x 1.6 = 56mm (some Canon DSLRs have a 1.3 multiplier though)