My advice try out all different play styles. Everyone is good at their own.
I solo majority of the time. Mostly i just look for 1v1's. Key thing for me is movement, it is the way you win 1v1's. Doesnt matter how your traited and what gear you have, if you cant hit the person because they are always at your back or even if its the opposite, if you can hit your opponent without being hit back, then they become useless.
Yeh its good to have the gear and all the knowledge. But learn to move well and you will find yourself winning alot of 1v1's.
The way i practise is i tend to run around with no armour, jewllery or sometimes even without a weapon aswell. Just to practise being able to hit them without getting hit back.
If you start to get good with gimping yourself, when you do use all you have you will see how good it is and you will be able to do alot better.
Use your mouse to turn (main thing). Also move some of your keys around, so you can have skills all around your movement keys, that definatly helped me. For me it helps to strafe alot, works well with mouse turning.
Anyway thats my advice, movement!