Welcome fellow APO resident!
Sounds like a nice setup.
First, your CPU temps seem a little hot, but in Japan that's understandable. I'd raise the CPU fan speed or reapply some Arctic Silver just to be safe. But if your system is stable under 100% load, don't worry about it so much.
Your video card is a good choice since you don't do much gaming. If you decide you need more video horsepower, get a Radeon 9500 pro with a Zalman HP80A (or newer). You won't regret it.
You don't mention any intake or exhaust fans. Don't you have any? I'd say you needed at least an exhaust.
I'd also recommend using elastomeric fan isolators for any case fans, and grommets for your hard drives/optical drives.
I'm not familiar with your motherboard, does it have a northbridge fan? If so, unplug it or get a Zalman NB cooler.
That's about it. If you have your case in a computer desk, you could set it on top of a piece of foam or a few old mouse pads to isolate it from the desk.
Enjoy the tropical weather while you can!