The method of dealing with Plaque build-up has been with abrasive toothpastes. This is a battle you will never win. The Streptococcus Mutans bacteria wins every time, creating more plaque every day for your dental hygienist to scrap away. It is in between your cleanings the damage is done and the bone loss that can occur is irreversible.
You have bought a soft toothbrush, but is it cleaning your teeth gently? The bristles and design need to be of high quality, so they do not splay out while you brush causing damage to your gums and enamel.
You mean well, but if you are brushing with too much force your are damaging the enamel of your teeth. Choose a quality toothbrush that has bristles that do not splay out while brushing.
Studies show that string floss only reaches 2mm to 3mm into the gum pockets and unless you really give it your best effort you are most likely only getting to the 2mm depth. Standard string floss also does nothing to address the bacteria that is creating your plaque. The practice of using standard string floss only transfers plaque bacteria throughout your mouth.