I like Vigilante a lot more than Deadpool personally. And while Gunn may have been influenced by Deadpool in some ways, Gunn's sense of humor is coming out more than anything else. I would love to see Vigilante teaming up with Rainn Wilson from Super.
In terms of it being a spin-off, I feel this show reflects the serial storytelling approach from comics. It feels very much like issues of a late-80s DC comic like Justice League International, taken a bit to the extreme with violence and lewd content of course. In that sense, it's a very different kind of story than the "one shot" story that a movie tells, but both have their place. And this one is being done right in my opinion.
Based on what I've seen so far, two of the three best live action superhero TV shows I've seen are on HBO Max (Peacemaker and Doom Patrol), the third being Daredevil. I have enjoyed all the Disney Plus shows to an extent, but they don't have that creative energy and excitement that the HBO shows do, and the willingness to challenge all conventions and do something new. And they are clearly are on the opposite end of the spectrum in terms of oversight by the powers that be. In Doom Patrol, one of the main characters' catch phrase is "What the ****???" and I don't think they had a single, conventional fighting scene in three seasons. When they do, they are zombie versions of themselves fighting man-eating butts or are really dealing with some deep psychological conflict. Even when Marvel goes the most outside of its comfort zone with something like Wandavision, it ends in the most conventional way.
For many years I've considered this to be the strength of DC. Sure, you will get a swing and a miss every now and then (e.g., first Suicide Squad, Snyderverse stuff, Jonah Hex), but with Marvel you would never get something like the Dark Knight or Peacemaker.