Pros
At most agencies, client services communicates the objectives, the ad ops department runs the campaign, and analytics handles the reporting. I've seen this lead to lack of ownership and information asymmetry. Those issues have yet to materialize at C-4. Autonomy and ownership are held at a premium. If you gain management's trust, they'll provide you with ample resources to develop your own working style and work on the projects that matter to you. If you can find a better way to do it, you're welcome to. The flexibility drives people to improve processes and reinvent the way things are done. At a small agency, every client matters. You get to know the people you're working for and learn their business objectives. When you help them succeed, your effort is appreciated. If you're good at what you do, the client-agency relationships are very rewarding. Rewarding work in itself is great, but only if you work with a good team. Everyone at C-4 is fun and laid back but serious when it comes to business. Beers on Fridays, ping pong, plenty of laughs and an overall camaraderie make work enjoyable.
Cons
Depending on how demanding your clients are, work-life balance can become an issue. Processes could also use improvement, but while those evolve, there needs to be more staff to handle the growing workload.