Pro Simplicity - it is made for everybody to use and love
Construct 2 is a tool for not just programmers, but artists as well. You can create a game with only visual coding, which is easy to learn and doesn't require any previous programming knowledge. You can focus on making your game better instead of just coding. It has some limitations of course, but it's definitely worth it.
Pro Rapid development
After using a few quick tutorials you can quickly catch on to the event system this program uses and quickly be able to build any type of 2D game you want. You can download a few sprites from google and put together a working level of Mega Man with character movement / animation / enemies / collision detection / scoring / Tile map and AI within about 2 hours.
The built in behaviors are incredible. It's amazing how Construct can simplify the most redundant tasks in game development.
Pro Allow server-less multiplayer game creation
Construct 2 uses WebRTC technology to support it's multiplayer functionality. The nature of the technology allows peer-to-peer connection which does not require game developer to create server side architecture to allow communication between games.
Pro In-depth event system
Construct 2's event system allows for deep, detailed control over all aspects of your game. You aren't limited to just a few options. Rather, Scirra has thought of nearly everything in advance with access to any desired parameter of any object all paired with simple and intuitive ways to interact with them.
Your events can be organized with event sheets (that can be included in other sheets), event groups, sub-events, loops, and functions that make the coding portion of your game as efficient as possible. You don't need any programming knowledge, but if you do have some, you'll feel right at home with the freedom C2 offers.
Pro Export control for all major platforms
All platform exporters are part of the subscription. There are no additional fees and new exporters are added quickly and maintained well. Currently, 15 platforms are supported, including HMTL 5, iOS, Android, Windows, Chrome Store, PhoneGap and Scirra.