Hey Myback this post is directed straight at you, but I'm putting it in the forums so others can comment.
I'm an entrepreneur / marketing / monetization guy. It's what I do and what I'm good at. I spend most of my time coding up projects that do things like drive traffic and make money.
Having put a lot of time into your server and enjoyed myself, I though I might reciprocate a little.
Here's how I think you can improve your server.
User Retention~
Code in a bloody tutorial. I've probably seen close to 100 users join RDM and quit once they get jailed. Literally every noob that joins this server has been programmed to do one thing in CS:GO... Kill..
They join, have no idea what to do, default to what they know, then get put in jail and quit because sitting in a box for 10 minutes is not fun. If they DO happen to return, they are put back in jail so they quit for good.
If they are lucky, they might get a long drawn out tutorial from another user that doesn't really want to do it in the first place, and therefore has a high chance of being dull / rushed / off-putting when doing it.
Get a tutorial to teach the basics, then let them figure out the rest through exploring and asking questions.
Come up with a tutorial that draws lines to vendors and teaches them step by step how to play. Teach them to plant / print. Send them to jail and let them out once you teach them about crime. etc.. etc.. Do this and your user retention / growth will explode.
Marketing
Market yourself man!
Try to find ways to get listed higher in the server listings, even if it means using bots to increase player count and coding the server to factor them out in plant speed.
Adjust your server title for common keywords.. remove fluff like "fast DL". Nobody searched for "Fast DL". Try adding in things like "RPG, 1v1, deathmatch, headshot" etc..
Abuse social media. Write a bot that tweets what's happening on the server and dress up the bot with a good design. Have it say things like "Murderous Morty just mugged Myback and stole 5,000 grams! #ESL" "laxative just jailed Murderous Morty! #CSGO #RPG" etc.. etc..
Monetization
This is trickier because I know you don't want a pay to win environment. Getting monthly subscribers is a decent start but you need more.
I would suggest a sales funnel of sorts. basically you get them comfortable giving you a small about of money. $2.50 for subscriber.. $0.50 for a cosmetic skin.. etc..
Then you work up the price, being sure to abuse addiction / gambling elements and excitement. Your crates are perfect for this.. $5 for a random crate.. $10 for a specific crate.. $25 for 8 crates. $50 for 15 crates.. etc.. etc.. give them a discount for buying in bulk and make getting specific crates worth more than random crates. Come up with reasonable prices but make sure to have larger packages. You might be surprised at how many players have jobs and are willing to pay $100 for crates after they've been playing for a week and have gotten totally addicted to your server.
Do all this and your server will become hella profitable.
GL.