Adding kelp, silica (monosilicic acid, not potassium silicate), and mollases, will help for sure and not interfere with Shaded's method.
Foliar of epsom works well too but I also havent had any issues with top dressing and watering, I have dabbled a bit in mixing epsom,
triacontanol, and fulvic acids in a foliar spray and havent seen any issues so far.
The extra manures will more greatly affect the nutrient balance so may cause you problems if you dont adjust the other fertilizers.
My buggest suggestion to you and all new growers is to not try too much at once, take the basics of Shaded's method, implement them and see how the plants grow for a round or two. Once you have a feel for the basics and can take your plant from veg through flower without any deficiencies then you can start to play with things.
If you try a bunch of things and keep changing things each time you will take a lot longer to get to the point of being able to take a plant from veg through flower while also spending extra money and time.
Gardening is a sport for the very patient.