This is a great piece Jack, thank you for taking the time to write it. I've been freelancing for five years around my full-time role and I've reached a point where I wan to go full-time freelance. Jobs are coming in without me advertising or having a proper website to sell my wares. I agree that the web design jobs are not drying up but just shifting focus and it’s up to you whether you follow suite with updated skills (what I'm doing now) or stay as you are and miss out on more work.
The biggest factor for not taking the plunge yet has been the scary nature of needing to bring in enough monthly to pay the mortgage and support my family. Looking at your figures and my own recent jobs I could easily take come double what I currently earn as a full-time designer/developer. I couldn't agree more that making good contacts and staying in touch is really important because you just don’t know who will send a job your way. I’ve personally had several web jobs come my way from a previous employer I left over 8 years ago!
Your article has been a real eye opener and given me confidence in my own abilities to just go for it…with lots of planning first of course! ;)