At the time, this was Ennis's farewell to the Punisher. That explains a few things, actually. Ennis is returning to a lighter tone after the darkness of Punisher MAX, although it's certainly not family-friendly. There's a character called Schitti. Genitals get torn off and eaten at the zoo, there's toilet, urine and masturbation humour and a man has sex with a pumpkin.
Also, the final episode self-consciously tries to be cool in a way that, in hindsight, feels like a farewell. The Punisher's one-liner in the opening splash page feels out-of-character, although it's a good one. (Is Frank even aware of supermodels? Does he distinguish between people he's not planning to kill?) Similarly, the boobs-and-bullets page is heralded with "this'll be the coolest footage of all time".
I don't mind any of that, though. As a goodbye, it fits. (More commercially, though, it was also a tie-in to the 2008 Punisher: War Zone movie that drew on Ennis's Punisher MAX run. It's also no longer a farewell to anything. Ennis returned for Punisher: The Platoon in 2017, while of course Dillon kept drawing the character, on and off, for the rest of his life.)
The plot's a direct sequel to Welcome Back, Frank, starring Ma Gnucci, Elite and Lieutenant von Richtofen. (Soap and the Russian are missing, though. We saw plenty of them in Marvel Knights.) Some of those familiar faces should be dead, as is normal for people who've met the Punisher, but there's an explanation for everything.
This story is everything you'd expect. Kills, kills and tasteless laughs. The graphic collections bundle it with Ennis's Marvel Knights run, rather than with the Punisher MAX stories it followed chronologically. It's good, disgusting fun. It has an oddity in von Richtofen possibly starting to become a serial killer... and then getting away with it as she helps the Punisher shoot baddies. Eh? Well, never mind. Dillon and Ennis is a perfect combination. The other Marvel Knights artists had all felt like temporary fill-ins for Steve Dillon. (I do like Tom Mandrake, though, while of course the walking bloody nightmares of Punisher MAX are a whole other level.)
Recommended, of course. I would say that, though, since I'm an Ennis fan.