More Half Life 2 goodness (and some thoughts re: RPGs)

I'm blowing through Half Life 2. It's obviously not as fun as the first time through, but there's enough excitement there to keep me going. And, I can't wait for the new content (Episodes 1 and 2). One thing I had forgotten -- the bridge sequence. I've felt vertigo in other games when I stood on the edge of a cliff. But this game takes that whole feeling to the next level. Emotionally, I felt as stressed out as I think I would actually feel if I were walking around the scaffolding of a bridge without any safety harness. It's that compelling.

Valve just gets so many other little things right, too. On the one hand they create core mechanics that are fun to execute over and over in the little sandboxes they set up. Every encounter is a puzzle that can be solved through the basic shooting, walking, jumping, and lifting actions of Gordon Freeman. On the other hand they script sequences that help advance the plot and add in some truly rewarding (and sometimes HFF) moments. Taken together, it is a wild ride that makes you really feel clever for solving puzzles even though (in the background) they are handing you the pieces and showing you ghost images of how to place them. You just never really notice it until you sit back and start to break it down. Impressive.

Switching gears, it's time to start thinking about RPGs again. Between Mass Effect, Eternal Sonata, Blue Dragon, and Puzzle Quest, I should be doing a fair amount of this kind of gaming in the near future. So, what are the components that make up a great RPG?

• Combat: Controls, Camera, Feedback. Feeling (moment-to-moment; preparation; post combat cleanup)
  
• Exploration: Where am I? Where do I want to go? Is getting there half the fun?
• Story advancement: Do I understand the story? Do I care about the story? Are my goals clear and interesting? How do I keep track of them?
  
• Character advancement: Do I get the right amount of leveling, choice, and growth?
• Environmental interaction: How do people and things react to me? How do my actions get reflected in the world? How does the world and its denizens communicate combat, exploration, story advancement, and character advancement to me?
• Economy: What are the collectibles (items, people, things)? How and when do I manage them? Are these all character based or is there some meta economy as well?
  
• Accessibility: How do we ensure that I get to see all the content? How do we solve for players getting lost or killed in battle?
  

I'm sure there's more. I'll need to work on refining this list as I go.