Avantages
If you are looking for a company that truly cares about you, this is the place. I have worked at a variety of agencies and none compare to attention and care I have experienced here. Everyone is kind and wants you to succeed.
The client portfolio is also very diverse and offers different verticals to get your hands on. There is also room to steer the ship in terms of new tools, resources, process, etc. The flexibility to choose your own path is something that was new to me coming from a very silo'd agency.
Inconvénients
Typical agency cons. Some weeks are harder than others and you will have to work some long hours here and there. (There has been an agency-wide initiative to mitigate this as best as possible.)
There can be a lack of process with the ability to shape the departments/clients. That is both a blessing and a curse if you value a bit more structure and clean process. (However, you can change this!)
There also seems to be a little disparity between higher level roles and lower level roles, not a bad thing per-say, just an observation.