I want to, for example, start a question to get a better feel for how advanced LAMP programmers tweak vim, specifically to highlight both PHP code and MySQL code. Is this a valid question to ask here, and if so where would I ask it?
Are you asking about a specific tweak? Because if you are, your question is on-topic at Stack Overflow (being a programming tool question).
If you're asking for a "list of things" (as in "What are the different ways you tweak Vim), your question is off-topic everywhere.