Certainly think that 2019 is probably the year I start looking at my career. It's quite a big step for me, as where I'm working now is where I truly started my career in IT/SQL Server, and I have a great group of friends and colleagues here. However, progression has certainly come to a stop recently, and I'm far too young to be complacent about not furthering my career.
Honestly, my first step for 2019 is probably contacting an Agency and getting advice on writing an IT based CV. I probably haven't written a CV in 10 years either, and back then it was Retail based, so I've literally no idea where to start. January i can use to brush up on how to write one, and a accompanying letter, and hopefully get the confidence to get some interviews. Your statement about "often just accepting the first [job] offer we get" is actually a very true Steve, and I thank you for reminding me that I should be interviewing the companies I go to. Finding a company that not only has options for progressions, but is up to date as well. I doubt I'd accept a job from a company using SQL Server 2008 still, and I'd love to be working somewhere where I can take advantage of SQL Server 2016+. Working with old tech doesn't help with progression as much, as we can't use the more modern tools that we read about and think "That would work wonders here!".
Not going to lie though, 2019 scares (is that the right word?) me quite a bit with Brexit on the horizon. Without trying to turn this topic political, Brexit is not in a good position at the moment; with no deal looking very likely, which is probably a worst case scenario. I get the idea that Britain could be a very different place to live as the year progresses. A bad Brexit is most definitely going to affect things like wages, and redundancies, and if you've just changed job you're far more likely to be in the firing line.
Excuse my typos and sometimes awful grammar. My fingers work faster than my brain does.