understanding the massive difference between 98%+1% and 50%+1%

This is one of the more valuable lessons that using logarithmic decibels, instead of linear probabilities, provides. Going from 98% to 99% adds 3 decibels; going from 50% to 51% adds 0.17 decibels.

Qualitative measures are fine - Lojban even has a 'number' word meaning 'about' ("ji'i"), and even getting a rough feel for the confidence-levels involved can be a step up from not having any idea at all, and is a step closer to having a better calibration for quantitative measures.