Well you can put your projects at work into your portfolio, given that you state clearly what area you worked on, and what is the company owning that project.

Also if you happen to write something during your free time. Something that doesn't really matter to you financially, you own the code, and you can open source it. You can put that on Github. It can help someone interested in hiring you to have more understanding about the level of your skills. You can also contribute something to open source project as well.

There's an old saying, "Those who can't write C++ are not game programmers". This is not necessary true anymore with the emergence of engines like Unity3D. However I think it helps if you know a little bit of C++ too, as majority of game engines are still written in C++. Try learning C++ a little bit, and may be how game engine works. That will help you understand more about game engine, including Unity 3D. One day you might have to work on a game engine itself, who knows ?

Probably not the advice you want to hear, but - if you're a family man - I'd seriously consider looking for alternatives outside game development (there's way more to development work than finance and commerce... not sure why that is always the go to example people contrast game development to...). Firstly, it's likely to pay you a lot better salary, secondly, it's likely to be a lot, lot more stable (unless you're with a really well-established company), and thirdly - you're more likely to have an employer that respects your time (though that depends on where you live and also the company - but the game industry is infamous for crunch and for treating developers as disposable - whereas good employers in the wider IT industry avoid it). Personally, the third has always been most important to me - I can always take my career in a new direction later, if I want to, but I'll never get another chance to be with my kids as they grow up.

Not clear to me whether you are in the industry already, or between jobs? If you're already in a job, focus on delivering value. Whenever I'm interviewing I'm looking for two things: 1) is the person smart? and 2) does he get things done? The first can sometimes be hard to demonstrate in an interview - it often depends on the interviewer. The second is "easy"; work on stuff that delivers value. If you're working big projects, try to agree with your managers to break them down into smaller deliverables (really, project management 101); that way, when you go to a future job interview, you can say "I worked on this game, and I delivered the core 3D engine, the physics engine, the skeletal animation, etc" rather than "I worked on this unfinished game...". If you're doing a small project for your portfolio, complete it (learn how to limit the scope of what you're doing so that you are able to complete it). A completed project, even of limited scope, is always a better than an ambitious, unfinished project.

Probably not the advice you want to hear, but - if you're a family man - I'd seriously consider looking for alternatives outside game development (there's way more to development work than finance and commerce... not sure why that is always the go to example people contrast game development to...). Firstly, it's likely to pay you a lot better salary, secondly, it's likely to be a lot, lot more stable (unless you're with a really well-established company), and thirdly - you're more likely to have an employer that respects your time (though that depends on where you live and also the company - but the game industry is infamous for crunch and for treating developers as disposable - whereas good employers in the wider IT industry avoid it). Personally, the third has always been most important to me - I can always take my career in a new direction later, if I want to, but I'll never get another chance to be with my kids as they grow up.

I can second this.

I spent 10 years in the financial industry (as a software developer, of course). While the work they give you can be extremely boring, like do only bug fixing for 10 years!, they do pay well and have better benefit. You will get scold if you do too much work, rather than spending you time with your family.

To my surprise, one of the company I know of (which will remain unnamed) decided to cut every employee's vacation down to bare legally-minimum. This will not happen in other IT company ever as they will lose their people. Some of the startups nowadays even give you unlimited vacation.

So why does this industry treat people differently than others? I think, people choose to work in game because of their passion. They want to get in because they love video games. So there will be more supplies than demands. This applies to games and players too, players don't pay well because they have so many game to choose from. Try comparing this to bank, people don't really love the numbers, so these company has to pay really well to retain people. Software developers are hard to find after all.

Anyway I've just got back to game industry, as I got bored from fixing bugs for a long long time :-).