First, LeoKing has a very agi oriented build, he has a few more points in shield than most other shielders, so dont take him as your example because he does not have an average build. Its like saying: Derp can 1hit me for someone with a 30-9 build or weaboo 121 can spam me for a 180 wpf katana build with good footwork...
Secondly, back hits are not blocked by hits, if you see so it probably is because of lag and the hit actually came from the front or the edge.
Thirdly, a decrease in shield weight would (at least for me) be a nerf, since weight is what helps you against crushthrough (together with shield skill)
Also, you cant move your shield around, and if you have to, then it is actually worse than manual blocking, so why would you bother? Ive been hit by people who start their swings in front of you then move around your shield and hit you around it (because of me failing at footwork in that situation), whereas irl the guy would have no problem putting the shield in the way...
Same way as in ranged, as you dont feel the weapon, you have the crosshair.
And what reasoning you put behind:
...
Shield skill should give you speed, maybe reduce the weight of your shield, and increase it's strengh,
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gives you speed: because you can move it around faster, as you know how to use it better. For the exact same reason, you can move it up and down and "reach" for those arrows.
reduce weight: as stated above, it would be a nerf against maulers, and why being more proficient makes it lighter? it makes no sense.
Increase strength: Why? Because you know how to put it to reduce the damage taken, but wait, its exactly the same point as for speed!!!
So, Blindguy, please open your eyes, and stop saying bullshit.