Starting a server is no joke. I started mine last March on my own and the first few month were brutal. But I dedicated my time and learned on how to improve. Overall, I've heard GMod is a dying community, and I guess that's true, but that's all I know in terms of in depth gaming lol (specifically ttt). But it worked out in the end, until it dies to the point where I'll simply let it die on its own. Regardless, I would let my servers die right now before I even considered selling Admin status.
Some tips from someone who was in your shoes (though I had IRL management experience coming into this):
1a. Don't bombard your server with every popular addon in the workshop. Your server is new. Give it a second to grow, and let users join at a good download time, and then over time try adding some popular addons more and more. This way you already have a good base for a community, and they'd be willing to stick around for the download times. First time joining with 100 downloads to get in with a fresh community sucks. Big time.
1b. Do keep in mind that people joining a server they've never joined before are looking for a new experience and are hoping for a positive experience overall. Long joining times diminishes that, and abusive, paid-for staff also diminishes that.
Personal suggestion: use _Undefined's pointshop, and add 1 or two models from workshop. Add 1 weapon pack as well, and then see how that goes.
2a. Don't accept bribes/money for admin status. I'm pretty bias in this aspect because I've actually managed staff before, but paying for a staff position in game is just silly. And granting people power for doing so is just as silly. Get to know your community, monitor behavior, and move from there.
2b. Do interact and communicate with the members of your community. Let your actions speak for you as well. If you expect to have a good staff, then you need to behave that way. Lead by example. If you find people who are also helping people, being friendly, and remaining active, then those are the people you'd most likely be able to trust with power. Not someone with Daddy's credit card ready to dime out subscription payments.
Personal suggestion: develop standards now so that they remain consistent throughout your stay as owner of the community, and can be passed on, if needed. Consistency in how you choose your staff will help improve consistency in who you recruit and the quality of the admin-ship you run in your community. You can check out my standards for various staff positions on my site. All positions laid out in advance fr the user to read through and understand what to expect, as well as what I expect from them.
http://mnwo.co/staffappsLast bit of advice: have fun. It's a game.
EDIT: I'm a Full Member now. Dope.
EDIT: And now I'm not...?