As you said in another post your pot mix is 5-1-1 reptibark - peat - perlite.
It possibly has low biological activity, except maybe some slight breaking down of the bark and peat.
I have used stimulant fertilisers, based on the type of things you mention, usually in conjunction with NPK plus trace, in soilless media.
Similar to what Piss P says.
You might consider worm liquid fertiliser, not worm castings as you don't need to intro worms to containers.
Zeolite, Humates and liquid kelp might be useful as well to stimulate and help with nutrient availability.
Molasses is used in fertiliser to stimulate soil biological activity. Not sure It's as useful in containers without an array of microbes to stimulate.
Overall if the pH of the pot mix is in the correct range, nutrients should be available.
Other forms of nutrients with different availability might overcome the pH problem, maybe not solve it.
Sometimes unless you re pot, mixes seem to get tired. I have found these type additions beneficial to boost plants without repotting.
I would also caution about trying too much at once, as containers are easy to add too, but difficult to remove from.