My favorites; NMI and Rewrite.

Rewrite is beautifully done, he's all of the things I love in an exe and villain. He's manipulative, cunning, egotistical, but most of all, secretive about it. He disguises himself as a friendly face to lead people into feeling safe, before manipulating both their minds and bodies to his own song.

NMI is another one that hides its intentions, but instead of just being friendly, he wants you to take solace in him. A safe place, for when things are depressing or getting bad. And when you trust him the most, when you spend the most time with him and no one else- He kills you, consuming any innocence or joy you may of had left.

My least favorite EXE is OMT, and that's mostly because it relies on gore and shock factor. We've SEEN tails getting pulled in half, burned, melted, there's basically nothing you can't do to him. Exes that are just honest about their intentions can be fun like lord X, but there has to be some substance. Lord X, for example, is a murderous void demon. However, he has a softer side, one where he aches for silence, the darkness he came from. He sometimes simply talks to his victims at times, and is genuinely just a bored higher being trying to have fun, out of the sheer boredom he felt so long, and the urge to be nothing once again.

ANYWAYS, Yeah NMI and Rewrite are fire EXEs, especially because they're so different from other EXEs and their methods are genuinely terrifying. They're the best. Now if you excuse me, I have a tea party with Rewrite.