Your best bet is to open a case with support. We can gather your requirements and create content requests with our patch content team.
Yep - what rdavidson said.
Any "new content requests" are by and large as simple as calling support & letting them know what product(s) you'd like to have added to the content team's list of things & then they investigate what / how they can best do that for the relevant vendor and product.
Silverlight I'd expect to see content for - it being a Microsoft product and so on though - but again, no harm in bumping that through support as well if you've got a specific need there .