Re: PHP - I have front-end experience including some of the emergent technologies such as Node.js etc.
Out of interest, what skills / technologies would make me more marketable to employers (overseas or otherwise)?
To make you more marketable to potential clients, I'd recommend focusing on some skills that are complimentary to programming. That may include domain-specific knowledge of a particular type of client you want to work with (e.g. bioscience, healthcare, local government) or it may include things like usability, SEO, or lead-generation. Find the profit centers in your clients business and find a way to get as close to those as possible. Learn the language they use to describe their work and make sure you use the same vocabulary when speaking with them.
Work for clients in high cost-of-living countries. Spend your time in lower cost-of-living countries.
Instant lifestyle upgrade.
Aren't you a little old to still be using PHP? ;)