Resurrection is as welcome here as insurrection. Thanks Slava. Actually I'd never noticed this topic before, but in hindsight my impression is that whatever paucity of response was perceived may come perhaps from a lack of understanding of the question.
The phrases given at the outset don't sound at all unusual to these eyes. Is it the intonation question alone then? Difficult to convey in the printed word but a logical answer might be that cadence is a far more subtle level of language and, if such accents seem arbitrary, may simply be secondary to the learning of the phrase itself. And the speakers thereof would naturally tend to impart their own native language's aural inflections.
And where some specific phrase may seem overly universal, consider this................
...I'd think similarly that it's more practical to learn single phrases for single ideas and move on to the next idea-phrase than to branch out to all its subtle variations. Until one achieves a deep fluency one will be severely limited in degree of expression in a second language- I could only imagine, but not execute, the challenge of translating this post into French, nuance and all.
Or put another way, a question of learning the words before the music.
As to "OK", it sounds like they're using it similarly to the Russian example (or Japanese
hai), but I'd think all languages have some version. We in US English, confronted with a statement on which we may not want to venture an opinion or affirmation, will simply offer an audible grunt or low moan, if not stargzer's "ooooh". A noncommittal 'message received', assurance that we haven't entirely zoned out on their trifling babble (yet).
What do you think about this one?
(Sluggo awaits responses of 'ah', 'huh', 'hai', and if the starts align just right, 'oooooh')
Being a language board we may tend to fixate on -and celebrate- the vagaries of wordplay, both intentional and unintentional, but we laugh together at the type, not individually at the typist. In my experience no one has demonstrated this on the receiving end more gracefully than gailr, so I'm sure no nag is intended. It's a simple refreshment when the music takes an unexpected turn. The best music is, after all, composed by accident.