Also, regarding people spamming (or hitting you twice before you can hit once) I notice that this definitely does happen. It is footwork, but also swing direction, weapon, and build.
Normally it is possible to strike back after you block if you are in the right position, but if you are facing an enemy with high athletics, high wpf, a fast weapon, AND good footwork...you will probably not be able to. If you get in the right position via footwork you can strike back...but against such an opponent it might take you 3, 4, or even 5 hits before you are able to wrestle the guy down and get in position for a strike.
What i mean is, it's not like "ok, i blocked a hit, now I need to get the right footwork and strike...oh shit I got hit again I guess it was bad footwork on my part lets wait for the next strike." It is likely that is was not even possible for you to get in the right position for the next strike because of the way your opponent was moving and the speed of his strikes. Sometimes you have no choice but to weather through a few attacks before you attack back, depending on your build (i'm speaking form experience in 5/6 athletics).
What does the "right position" look like? I don't know, I'm still kind of feeling that out and going on gut instinct.
TL;DR?
I feel like I'm rambling on, but what I'm trying to say is not every step your enemy makes has an appropriate counter-step you can take to ensure you will be able to hit him after you block. He may be much faster moving, or much faster swinging (or both) and can put you (through
his footwork) into positions where you CAN be spammed, and because of your lower athletics or wpf you can do nothing about this until you get in to position to strike...which is always possible if you have the patience and the practice.
Tip for getting in the right position:
As a shielder this can be tough for me, but this tip can work for anyone. Use the terrain and surroundings. Get them on to an incline, or into a hallway, bridge, against a wall, or even near a tree. This limits their footwork options and lets you get in position easier.