I won't say a word about Q.
The Borg are described as "a force of nature" and are basically top dawg, so idk wtf choo talkin 'bout.
I adore species 8472 and Kes. (There is a novel where Kes becomes a crystalline (like) entity and collects world-destroying dark-matter. Fun stuff.)
The Year of Hell (part 2, especially) has a genuinely compelling (if archetypal) character fumbling to correct past mistakes.
Demon opens up a few truly interesting questions, and has my favorite line from Tom Paris ever: Until I met him, I really thought I was Tom Paris! It was a
Spoiler:
(Deuterium based-lifeform doppleganger).
Sure Nelix is a poop, but Torres has an actual character arc without needing a bat'leth or positronic brain.
And I think that Naiomi Wildman would beat up Alexander Rozhenko.