I usually have decent success with pickup parties, its usually because floors >50 are not obtained by not good at nyzul people. Also, you only need 2 people who know what they're doing to actually succeed(at a climb anyway). The rest just need to be able to follow 1 or 2 simple instructions and you're golden (usually "everyone touch the lamp", or "kill this").
Also, doing nyzul for the expressed purpose of farming weapons is a waste of time. You need to climb reasonably high to unlock them within the realm of practicality anyway (in doing so, you'll probably get the weapon too).
NIN75 BLU75 MNK75 DNC75 SAM75
Aurora - Linkaga