Ah, but let me take issue with some of that.
First I heard One Piece was foisted on 4Kids by Toei, who made them take it as part of a package deal. I think 4Kids knew it is was aimed at an older audience than their usual fare., but mistakes were made.
The only prominent human female character was April and for some reason, she wore a crop top, even in situations where that would make no sense. There is a scene where she is in a lab, with a lab coat and a crop top, its like the image for the ''Hot Scientist'' on TV Tropes:
Hot Scientist - TV Tropes
It not may be as fan servicery as the One Piece, but putting her in a crop top in setting where it makes no sense, seems to be putting fan servicey outfits over what someone should wear in that situation. I think that is suggestive attire, almost to point of defying logic in some situations.
I do not think the TMNT or Spinter are Christians, April may be, but that is never really said in the Mirage comics, so there wouldn't be any crosses regardless.
The TMNT are too young to be drinking, I think in the Mirage comics April would have the occasional glass of wine and Casey would have a beer sometimes, but that was not a huge part of their character. The biggest drinker from the comics is April's sister Robyn, who was very disorganized compared to April and she only appeared in one episode of the 4Kids series. Also, I am not sure I have ever seen anyone smoke in the Mirage comics, there was villain in the Archie comics who had a cigar, a vile villain named Mr. Null, who I think is interesting, but likely will not show in animation any time soon and is from a but that is a different continuity.
TMNT actually would occasionally mention something beyond the surface level in regards to Japan, like Shredder mentioning the conquest of Japan by the Tokugawa clan, heck that is something that is actually educational and interesting. Its more than they let into the Pokemon dub.
Yeah no blood in this series, but Donnie did kill Shredder with a giant drill in ''Same As it Never Was'', he was an alien, but you get see him die. There was also an episode called ''Insane in the Membrane'', which just featured body horror, I think the network didn't let that one air, it did air in other countries, but still 4Kids made it and it's pretty out there, April kicks a rotting Baxter Stockman and dislocates his jaw.
The gun thing I can agree with, with all the recent gun violence in America, I doubt you will see realistic guns in kids cartoons any time soon. This is less of an issue in Japan, which has really strict gun laws.