Ok, now I understand... typically the word 'Mary Sue' is used to describe a poorly written protagonist, not an enemy type... the word 'overpowered' or OP for short would've gotten the message across much better.
And yes, I've already taken this into account. You would've known this had you have read this following quote from my Dantooine leak.
So yes, they will be tested before release to ensure they can be defeated. It'd be considered a bug if they couldn't.
Jedi Diversity on the Star Forge should work fine when installed after the NPC Diversity Pack mod, though any future NPC mod I make which affects Jedi would have to be installed before Jedi Diversity on the Star Forge.
Dark Jedi Wear Robes is different, however, the reason it's different is that the NPC Diversity Pack swaps some of the Dark Jedi trio encounters with the Dark Jedi Master appearances from the Dark Side ending. You can install Dark Jedi Wear Robes after the NPC Diversity Pack if you want, but the worst I can see happen is that some Dark Jedi might have DP's unique Dark Jedi Master appearances and this might not look very good considering one of them is literally Darth Malgus.