Both seasons do start a little slow. The second season is a bit less of a grind in the sense that the first season has a lot of story to build. But the conclusion to season one is one of the best I've seen.
Season 2 moves along a little better. I did not like the season 2 conclusion as much, but it does have a good amount of closure to it.
All in all the show is very good and i think this is the best version of the punisher so far, even though this version doesn't really feel like the punisher. Honestly, this show NEEDS a season 3 before Netflix loses it to Disney like all the other Marvel shows it was making.
Throughout the majority of the series when i watch Netflix' The Punisher it feels like I'm watching a more violent R rated version of Sons of Anarchy, except without the motorcycles. The story is actually pretty good, the action is very well done, and all of the actors did a great job. Though, I would have liked Frank to embrace the punisher persona sooner