Unfortunately I've only played the standard and the spin. I have the rough currently in a gut/poly hybrid but I doubt I can make a solid comparison given it's my first time playing gut. However, based on what I've seen I can attempt to explain.
Firstly, the original Luxilon string was Big Banger, from which ALU Power derived. The full name is actually Big Banger ALU Power, it's just a string from the Big Banger line of strings and the most popular one.
Now to the varieties:
The first ALU Power was released in a silver color in 1994 and is now the most popular string on the tour due to having a strong following after Guga Kuerten won Roland Garros with it 3 times.
Eventually the Ice Blue version (my favorite) was released, and this new colorway was softer and deader feeling, with more control and spin than the original but it didn't catch on as much because it was less lovely and crisp than the silver colorway.
At some point the rough version was also released, and the texture on it makes the string play slightly thinner while also grabbing the ball a but more and being softer. However this also makes the string less consistent because sometimes you hit a groove and sometimes you don't.
Now the feel version is just a thinner version, so there's not much to say about that, and the fluoro version has some fluorinated additive during extrusion which is supposed to enhance comfort and it's also slightly thinner than the original.
The spin version has a pentagonal shape which is meant to enhance spin potential and it also comes in a slightly thicker gauge. I didn't like this string's inconsistent response compared to the original/ice versions and it didn't seem to provide me with extra spin. That's my subjective experience though.
Finally, ALU Power Soft was released a couple years ago, with some additives to make it slightly softer than the original. Interestingly, these additives also seem to have made the soft version slicker than the original and therefore more spin friendly. I tried the soft counterpart to 4G and found exactly that; slightly but not much softer, slicker and with much better spin potential and feel.
I hope I could help