Hi Scott,
You should get good exposures in any AE mode, matrix metering,
manually selected ISO (you can use lower ISO at shorter distances under 20-30', and increase the working distance with higher ISO settings. The popup flash has a GN of 13 (m at ISO 100) so it's rated as adequate to about 40' at ISO 100 -- YMMV though, and rated GN is notoriously optimistic. Either manually select flash WB or set the camera to choose Flash WB when flash is used in the menus. The second option is the easiest since you don't have to remember to reset the WB after your done using the flash.
Green mode is not a choice that I would make because it may default to image settings that I don't particularly prefer. I don't think I've ever used Green mode. . .
One thing to try is to
enable "Link AE to AF" point when using flash. Linking the AE to the AF point allows the flash exposure system to recognize the subject that you focused on as the subject to be exposed properly. You can either use center point AF or choose your focus point with SEL mode for more creative composition, and you'll still be good.
The camera should default to 1/180 or slower whenever you pop the flash up, so you shouldn't have to worry about it. The only exception would be if you're using an external flash and have a HSS option.
I've always found P=TTL to be reliable and brainless (which is very good for me
), except in some specific circumstances like "blinkers" who always blink at the preflash and when shooting directly at a highly reflective surface where the reflection of the preflash confuses the metering system and causes massive underexposure. In the first case, you need to use a manual flash or one that has an Auto Thyristor sensor and doesn't use a preflash, or shoot available light. For the second, you can train yourself to look for the preflash, and if you see a bright reflection right before the mirror flips up and blacks out the VF, you know immediately that you have to take a step or two to the side and reshoot.
Another problem that crops up is when one person at a party is very close, but your main subject is further away. Remember that light intensity falls off in an inverse square relationship to the distance, so the flash's intensity falls off quickly. If something in the frame is considerably closer than what your camera is metering for, then it's going to be blown out. Let it meter for your subject and try to keep everything in the frame at a similar distance if possible. If this is not possible, then get an external flash and bounce off the ceiling, illuminating everything in the room similarly.
Flash can be your friend. Learn how P-TTL "thinks" and use it to your advantage. Many people seem to assume that it can't work reliably, and then grumble when it doesn't work as they expect it to. This is digital photgraphy . . .experiment with it with the only cost being some battery power
before the event you want to shoot, then use it with confidence.
One more thing -- P-TTL seems to like medium apertures better than very fast or very small ones -- there is a slight tendency to overexpose at very wide apertures and underexpose very tight ones -- try this out and find out how your particular camera reacts to different apertures.
Scott