I'll steal a line from Chris Fitz's video series. The bass players priorities should be time, form, and groove. In bluegrass, all three are accomplished with R-5 90% of the time. Your job isn't melody or swing lol.[/QUOTE]
My priorities are the same (I think): time, intonation (form?), musicality (groove?), or at least similar. And in 30 years' playing in bluegrass settings, I accomplish all three without playing R-5 90% of the time. Probably 50%. I'm concerned anytime someone makes a sweeping generalization; I always think of the old adage "the only accurate generalization is the one that states 'generalizations are seldom accurate'." In a straight-ahead, I-IV-V, traditional song R-5 is the best choice behind the verse and instrumental break; but there is certainly a place for a more musical style behind the chorus. Step out of the traditional vein, but still bluegrass, and the opportunities expand. And that does not include playing the melody (we certainly agree on that).
But in the end, it's all subjective. What works for me may be heresy for another. The good news is we're both having fun. And our style probably supports the needs of the people we play with. I guess I've been fortunate in that the people I play with ask for, and appreciate, a different style of bass.