Where can I go to make enhancement/feature requests for OSX Lion?
Here's the official Feedback form for OS X.

http://www.apple.com/feedback/macosx.html

The general feedback pages do get to the marketing and engineering people as well as measuring user satisfaction, but you also can sign up for a free developer account and file bugs more directly with the engineering team. It's best to reserve this for real bugs, but it's also appropriate to make usability / functional requests there too.

http://bugreporter.apple.com

Your issue where you can repeatably break a known function is clearly a bug and might get resolved much faster through the bug channel. You can upload specifics of your hardware and steps to reproduce and honest bugs get resolved quite efficiently through this channel.