I am not a native speaker of any spoken Chinese dialect but wished to understand public media and have an ability to speak comparable to my English fluency. I had chosen Cantonese over Mandarin for this purpose for three reasons. First I understand Cantonese to be closer to the spoken language of the classics and secondly that it is the lingua franca of the overseas Chinese. Finally it is the dialect common in Hong Kong, Macao, and Taiwan as well as the native tongue of my friend Joe Shen. Ultimately however, simplified putonghua, is the reasonable choice.
The first of these reasons should and is reported to in fact make it the case that Cantonese speakers understand Mandarin with much greater ease than the reverse. We shall see, but in my case the point is somewhat moot:
From the start my language goals call for a unification of the convergent languages in Ren Wen at the level of the human language facility. In particular while we accept as a start the Hanzi and sound system of modern standard Chinese, we are more concerned with abstracting their technical properties in formation of the interlingua. This personal spoken variant of 'Chinese' is what we really mean when we say "Cantonese" or <<秦>>.
We project 10 years from this writing to do so, i.e. c 4728.