I'm not a fan of Deadpool and haven't read Spawn in yonks so I'd rather they didn't have much of a future. There have been other, and in my opinion, better vigilantes in comics. In American comics, Spidey and Batman were both considered outside the law and, certainly in Spidey's early days, were pursued by the law. Currently, Dynamite's versions of The Spider and The Shadow are, imo, much better examples of outside the law vigilantes and for the most part, they always have been.
There are other examples but if you want serious anti-heroes, have a look at some of the Italian creations:- Kriminal, Satanik, Sadik, Diabolik, Zakimort etc. Some, e.g. Sadik were out and out violent, sadistic criminals, others e.g. Zakimort were often or at times almost fighting for justice. American comics had Grips, who was what Wolverine should have been. But that was small press and bad management and didn't take off. British comics and story papers had their share of anti-heroes and you should have a look at The Black Sapper, one of a number of villains later turned heroes.
I'm sure the 2 characters you mention have legions of fans, so my lack of appreciation for them is a drop in the ocean
The serials of The Shadow, Spider, Batman and the films of Diabolik, Kriminal, Satanik are well worth a watch