PeterMollenburg wrote:1.) Pronunciation
Good point about pronunciation guides for tones and stress. I can speculate on why it's lacking in learning materials.
Tones:
I think tones in Norwegian is seen as something not important and in fact totally superfluous because it's not vital for understanding like the tones in Chinese. I suspect most Norwegians are not aware of tones in the language - they might have heard that our language has tones, but couldn't tell you what tone a particular word has. Because if you haven't trained your ear for it it's not easy to hear. There's no tradition for teaching this and apparantly it's hard to find a systematic ordering and overview on this aspect of the language.
Stress markings should be notated because they are important to get right, but it could be that there are rules that you can follow to deduce stress patterns
I think it's laudable that you want to get the pronunciation right, but at the same time we as learners have to accept that we will sound like foreigners when speaking. This perfectionist attitude might be the reason that many (some) native English speakers in Norway continue speaking English, even after 10 years. Usually they understand perfectly well, but avoid speaking Norwegian, something that I find slightly annoying.
PeterMollenburg wrote:2.) Dialects
Gender: I didn't know that masculine and feminine are lumped together. That hurts my language sensibility, even if I know that it has disappeared in some dialects.
There's definitely a tacitly accepted standard pronunciation in the "neutral Oslo speech". Be aware that there are several sosiolects in Oslo as well.
All the other dialects could be a challenge. I think studying Nynorsk as well should prepare you for understanding dialects.
But it's not like Norwegian is the only language with dialects. In Spanish there's (at least) the difference between standard castellano and andalucian which you have to get used to. German has widely varying dialects - but they're not that much used. Britain certainly has a wide range of dialects.