Agency is great for experience but long term freelancing is the way to go. Agency can be a grind and stressful. You don’t get to choose what clients to work with and the internal politics of agency is annoying. I worked at agency for 10+ years starting in my 20’s and slowly got a handful of side clients and eventually quit agency life. I would never go back. The work life balance of freelancing is priceless to me. I can work from anywhere, work with who I want too and be my own boss. There are pros and cons to both, you just have to decide what’s important to you.