This iteration of the rule looks really good. My only raised eyebrow would be over the prohibition of prone figures reacting. Hoping for a reaction to save a fallen character from certain doom has added a lot of tension to our recent games: will he be able to stand up before the hacking mob does its grisly work? Will he get a chance, and will he make the roll?
The choice of turnover or two reactions is very elegant and irons out the most complicated (to explain) aspect of our house-ruled playtests. For a game with more than two players, a mandatory turnover would make sense, though.
On the slow restriction: this looks good, but presumably there will only be reactions on more than one die when there's a choice of turnover. I wonder if it's even worth having the restriction at all, given that the Slow figure's restriction to one move would still apply. So a giant who was able to react on three dice could move and do a power blow, but not move twice. Isn't this extending Slowness beyond movement to other actions? And won't it very rarely arise and thus be easy to forget? I think "forgettability" is a good test of a rule.
Andy, we used goblins in our last two games and they worked pretty well. The numbers of potential reactors seemed to balance out the lesser chance of a reaction. Once you throw leaders into the mix, the quality tends to balance out anyway, and then having lots of figures who can react meaningfully really helps. So, if you have a bunch of goblins close to the action, there's the opportunity to shoot with one reaction and then shoot lethally at the fallen foe with the next, for example. The Gang trait also means that you can have a lot of models close to the action and ready to help each other out.
Certainly, lower-quality troops are less capable without a leader, but that seems to me to be as it should be. One thing I love about the Ganesha rules is that Orcs behave Orcishly, in that they're menacing with a leader, but prone to flight when he's killed. I always think of certain passages in Tolkien when my goblins flee. It may be small consolation, but at least it rings true!
"Suddenly a sword flashed in its own light. Bilbo saw it go right through the Great Goblin as he stood dumbfounded in the middle of his rage. He fell dead, and the goblin soldiers fled before the sword shrieking into the darkness."
"He scattered the bodyguard and pulled down Bolg himself and crushed him. Then dismay fell on the Goblins and they fled in all directions."
"The orc fell with cloven head. His followers fled howling, as Boromir and Aragorn sprang at them."
"Aragorn smote to the ground the captain that stood in his path, and the rest fled in terror of his wrath."
Labouring the point a bit, but I think SOBH/FiFu does genuinely give you goblins that act like goblins!