Sounds good! Be careful though... All these additional adjustments you're adding to the water are temporary. After each water change your parameters will be fluctuating again which will be dangerous for the fish and shrimp.
I'm not sure what the leaves and alder cones (what are they?) do to your algae and if they can cause the film on top of the water? Do you have a picture of that film?
The best thing is to just slowly build it up. Not add all plants at the same time and give the filter the time to develop the necessary bacteria. Keep it a plants only aquarium for the upcoming weeks would be my advice.