You didn't clear up my confusion about [r] elsewhere, though. I'm 100 % sure most Dutch I've heard is full of [r] at least in other places, like the /r/ in ‹voor›. Is this wrong? By this I don't mean "will people understand me?", but "do the natives themselves do it, and how common is it, and why is it this is why I've heard the most if it isn't the most common (if that is the case)?".
Sorry for the late reply. I haven't been here for ages.
I'm afraid I can't answer accurately because I'm not a native speaker.
If you say [r] everywhere, that will do it. If you say [R], make it clear that it is not a [x] (so don't say g/ch like you say r).
In general, there are plenty of accents/dialects. Sometimes two Dutch speakers can't understand each other while speaking their mother tongue, so they switch to English (true story). When Dutch people show Flemish people speaking on TV, they subtitle them (the same goes for Dutch people speaking on Flemish TV). But the written language is pretty much the same.
What I can advise is try to listen to people from the area you like and stick to their pronunciation. Avoid mixing all pronunciations...
Or, you can just listen to the national broadcasting and try to imitate their pronunciation.
It's been a century that Flemish and Dutch are building separate Ausbau, accentuating their differences. Flemish are creating a common language based on the rules of the most central dialect (brabants) and a Flemish pronunciation. So for example they say things like "nen" instead of "een" in the masculine, because it works more like German. (...But that has nothing to do with this thread.)