A lot of people on these boards come up with nerf cries on a regular basis. Many of these nerf cries are directed towards a few professions, often because of an ability that makes them powerful in PvP.
But as history tells us, if you nerf a profession too much, they start to vanish, at least at high levels. So - and I encourage other people to chime in with their own ideas - I'm going to try to imagine Rubi-Ka without...
High-Level Traders: Wow, it sure is hard to find a wrangle these days. You've been trying to get your new QL 200 gun on for three hours now, you've got your implants in and everything, but you just can't find a trader who can and will do the 132 wrangle you need. Another hour later and you give up in disgust, slapping on a gun you can self-equip.
A few days later you've finally gotten your gun on, paying 500k for a wrangle, and you unleash a world of hurt on an enemy NT who's been area nuking your guild and killing lots of people, hoping to finish him off. But - darn - a doctor on his side just complete-healed him. You spam the tactical channel looking for someone to debuff that doc... but there aren't any traders, and oh yeah, drains were nerfed so much it wouldn't have mattered if there were.
High-Level Fixers: Well, it's come time for you to do a unique. You want some phat uber lewt, and you need a tank. The best tank for this unique is a GA4 fixer... only, you don't know any that still play. In fact, if your friend hadn't relogged to buff your teams' NCUs, you wouldn't even have that much. You try to get an enforcer to tank the encounter, but after the latest round of PVP nerfs hit them, high level enforcers are pretty hard to find too.
High-Level Doctors: You convinced an agent friend to FP doctor so you can get your implants on, but your guild hasn't managed to kill a unique in three weeks. Ever since the doctors either stopped leveling at 149 because of the PvP brackets, or just plain quit or switched to alts because of the nerfs, only a very few of the bosses have been dying, and mostly just to large guilds who are forcing people to play doctors or using docs on second accounts for it. It's been kind of rough in the notum wars lately as well - without docs around to keep you healed, you're spending more time than ever at reclaim.
Those are just a few examples... think about it before you start screaming your head off for more nerfing. How hard is it to find a high level MP? Do you really want it to be that hard to find a trader or a doctor or a tank?