The worst thing of the every game is the 10-15% or less values. Same to 85-90% and higher. You ought to use them as 0 or 100 percent chance and load the save otherwise.
So, it's fine to have close to 50% probabilities. For other cases "always" or "never" is better.
For example, this game have a "crit chance" value. You have less than 15% on low levels. So, it is better to not account this value in your planning. Imo, it is better to have constant 50% crit chance. And different crit damage, based on your weapon, skills, stats.
This makes game less predictable every action, and this is times better than rare cases of "something going times better/worse than expected".