Yup, that is very similar to my experience as well. One of the good things is, that here a lot is done by just people banding together. Some of the things you mentioned?

• Greeters? — #projectnewbie
• Mentoring? — #steemprentice

There are some things, that could be done also, one of them is improving the UI to improve UX, but I really hope that guys from #golos, will send their UI stuff upstream, since making better UX is one of their stated goals. :)

So, if you have an idea, try to find some other people interested in helping out, and fill that niche, that is one of the lessons I've learned from Steemit, and I hope that helps.
Some of my cool ideas sunk, because at the time I was unable to utilize the network effect, but the team I am working with @rusteemitblog, we are pushing #spreadthepower, in that the rewards that posts get are used to powerup the translators. While they aren't significant yet, it was still something that kept me going on, because at the time my posts usually haven't broken $1.
Even now, if my posts bring me ~$5 consistently, that would make me happy, but at least being active on Steemit somehow landed me a job, which is another good thing, that can happen. :-D Best part about it? I am in Siberia, my employers are in central Russia & moving a lot, but we can colaborate over the internet. :-D