I'll be honest, while the whole Leto joker package (tats, grills, clothing, etc) is not something I ever hoped for or predicted for this version, I am absolutely loving it all at this point. From what I can tell, it all comes together really well.
He's everything The Joker should be. Creepy, gaudy, deranged, over-the-top, violent, unhinged, and a showman. A tattoo doesn't change or take away from any of that. And while the same people have gone on and on about how distracting the tattoos and grills are, how perfect his look would be if it didn't have those things, I disagree.
If you're talking about a strict adaptation/translation of The Joker's comic book appearance, then yes, it would be just about "perfect" and "comic accurate" without those things. However, in this case, I'm starting to actually feel that they add something to his whole aesthetic. It all just clicks, especially when seeing him in action. It's something that gives him a distinct, unique look compared to previous iterations, but overall, he's still very much "The Joker" we all know and love.