Thanks for the reply.
My reason for asking for SP2013 specific alternatives was actually the fact that I needed some of the things SP2013 workflows do well OOTB (loops, for example). Since posting this, I've discovered the Actions that make use of the interop functionality to
start and wait for SP2010 workflows from within a SP2013 workflow, so that's the solution I'm using at the moment. It's not ideal, but it works.
Still, I'm quite disheartened by the lack in SP2013 of features that made SP2010 workflows so powerful and easy to use OOTB. It probably all fits into a bigger picture, but I wish Microsoft would share more details with partners about design decisions like
this and the vision and roadmap it has for products such as Infopath. At the moment, due to numerous reasons, I feel like the only viable way to go is to advise my team to go for custom workflow development in Visual Studio for future projects.