I think you should do what works for you best. With my RFs I mostly use full manual mode guided by a center weighted light reading, then I adjust the exposure from there, depending on the situation.
For example, if I take a picture of a subject with strong backlight I take a center weighted reading but know that the main subject will be overexposed. So I just open the apperture up a bit, or add some time, knowing that the apperture influences the depth of field. If I was just looking for the silhouette, I could have left everything as is. In this process it is good to know how your meter works and what it 'sees' and to know how the apperture influences your depth of field.
Plenty of ways are leading to Rome. For example, I could also have taken a spot reading of the subject if I wanted it to be exposed around 18% grey.
Use what is most comfortable for you. I do not think that full manual mode is the key. The most important thing is that you are feeling comfortable with your camera and develop a sense for predictability of the results depending on your preferences and settings, be it manual, shutter-, apperture priority, full automatic mode with exposure compensation or a combiation thereof, depending of the situation.
However, I would alway recommend a camera, that allows for adjusting shutter speed and apperture independently, as it gives you the most flexibility. If I had the choice between a camera with apperture priority mode only and fully manual, I would always choose the manual camera, given that the rest of the features were more or less similar.
Be flexible, relax, get acquainted with your gear, experiment and do not be deterred if something does not turn out as you supposed it to turn out in the first place. Surprises can be pleasent and also instrucive.