Before you start using an RNG (random number generator) you need to have solid plan when we want to mix things up like you said. You need a lot of experience to have a clue about this and so i think you should make your life much easier at NL10 and simplyify your strategy a lot. The air aint that thin at this level.
However there is some spots that are quite obv. and where an RNG makes sense to also make your life easier:
like holding KJ as the PFraiser ip on AK2r
Here we can and should cbet and X sometimes and the RNG makes it easy to become indifferent.
But dont think about the complex XR-riverspots where these decisions make sense to split up as well: AT NL10 the answer here is usally much easier than any RNG might suggest

Mixed frequencies come about when the EV of 2 or more possible actions is equal, this is highly sensitive to correct play from your opponents. Small changes in their strategy that may seem inconsequential are often significant enough that your hands start to take binary responses. Randomising is important when you are unable to correctly predict the mistakes your opponent makes AND they are able to exploit you for playing a pure instead of mixed strategy however neither of these things is true of 10nl.

What you should focus on is understanding why a mixed strategy comes about and then which of these possible reasons the villains in your games may be neglecting, actually nailing the mixed strategy is a secondary concern. One place that you may want to use mixed strategies even if you think you may have an idea of the tendencies of your opponent is, as mentioned, when you CB the flop because you will want to have a variety of hands in different lines because they might be making bigger errors in some part of the game tree than just over folding to your CB (i.e: over stab vs missed CB which you never find out if you just bet everything when you shouldn't).