There are basically 4 types of luggage you could travel with: a backpack, a duffle bag, a small suitcase, a big suitcase (or more). All have their pros and cons and each of them will be more adapted to a different type of travel.
Travelling with a Duffle Bag
Travelling with a Small Suitcase
Now of course, it’s small so you need to limit yourself, especially if you take it as a carry-on as it means you are limited in weight. And if you’re not in a nice city (and even then) and on the move you might end up having to actually carry it as there can be many obstacles on the way to a smooth rolling.
The small suitcase will therefore be your best friend for short trips mainly in urban areas or whenever you can drop it somewhere and go explore.
Travelling with a big suitcase (or more)
Yet be careful not to exceed the plane limitation for checked-in luggage as these can become heavy pretty fast! And the main inconvenient is logical: it can become heavy pretty fast! So that will be your option if you just need to go from point A to B and not move anymore! Perfect for resort holidays or a week skiing. Avoid absolutely if you plan to stay in different places and you don’t have a car (yours or a taxi).
Travelling with a Backpack
Of course it also means that you have to limit yourself in what to bring, first because you have a limited amount of space available, second because you will need to carry it on your back! It may also not be suited if you need to pack some fancy/ fragile clothes as it may not be easy to pack them in a very flat and careful manner.
However backpacks are definitely your option if you are planning on hiking, camping, go on a nomadic journey and move from one place to the other every other day.
And of course it’s the world traveler best friend.