Congratulations on your new purchase and thanks for sharing your first impressions, and good to see you getting out and about to make good use of the camera.
Regarding:
-There are some weird features like "Link AE and AF Point"... etc
Link AE and AF Point
Yes you've stumbled upon a particularly confusing feature there (because it is only skimmed over in the manual) and many folks have documented conflicting assumptions about what it does.
As far as I can tell, the following is correct, but I recently sold most of my gear (ready for buying new) so don't have a GR to test it on at the moment.
Back in the day, both Matrix Metering and Spot Metering were hardware dependent. Matrix Metering had its own fixed pattern to meter different segments across the frame and make a reading based on combing the different values from the different segments.
Similarly spot metering used a small fixed segment in the centre of the frame to obtain the reading, so spot metering required use of the centre spot.
When Ricoh went digital, they based their settings around what traditional photographers were used to.
So matrix metering uses a fixed segments across the frame (but from the sensor), while spot metering uses a small centre segment (but from sensor).
Turning on "Link AE and AF Point" has the following effect:
Matrix Metering: The
segment containing the AF point is given higher priority when the values from the different segments are combined into the resulting meter reading.
Spot Metering: A small segment centred on the AF point is used as the spot segment for taking the meter reading.
Highlight Weighted Metering
This is a very useful feature, it will basically underexpose the image (compared to regular matrix metering) such that bright highlights are not completely blown.
Different people use it in different ways, the site linked to earlier in the thread used it in conjunction with high contrast B&W JPEGs which resulted in images with little or no shadow detail, but that's just one way to use it, a way that is great for JPEG shooters because it gives a reliable way of avoiding blown highlights.
But when shooting raw you can make use of it in other ways. The blown highlights in JPEGs is often the result of the tone curve applied to the image during raw processing. The raw itself may have captured additional highlight data which doesn't make it through to the processed JPEG, but which can be recovered from the raw file (this extra highlight data is usually called raw headroom)
As its name suggests, Highlight Weighted Metering favours capturing (not blowing) highlights, but as this is done by reducing exposure, it has a detrimental effect to the shadows and means it fails to make use of any raw headroom.
However, you can use exposure compensation to change that. By using HWM to weight for highlights and then adding (for example) +1EV to the exposure with exposure compensation, you can then make use of the raw headroom such that highlights are still preserved in raw and then get more use from the shadows thanks to the extra stop of exposure.
Ideally you would first test this in your typical lighting scenarios to work out where the limits are. It might be more than +1EV in some scenarios but less in others.
Enjoy you new camera!
