Yes, maintainability is key. But, the technology used is only part of the choice. The actual design of the solution is probably more important. If it is designed well, and documented as needed, then it should be easy to understand.
I'm often reminded of Code Complete by Steve McConnell... The one thing that most stood out to me from this book was that a particular tool or technology may or may not natively support good coding practices, but a good developer (or DBA) knows how to implement good coding practices anyway and will find ways to work within the chosen technology. For example, T-SQL does not natively support the ideal of constants, but that does not mean I can't use variables in my T-SQL as constants to improve readability and maintainability.
This is why I say that the design, and good coding practice, are more important than a particular technology.
MKE Data Guy