Newb
Remember, you're making this for the customer's enjoyment first. Be proud of your work, but without people making requests, improving is a lot harder, and the only way to continue to get customers is to continually step up your game.
I separate myself from other poster makers by offering
extremely low prices for high quality work and only asking for any required payment after I have finished the work. I specialize in quality and efficiency, as well as Team Posters. I can usually get a poster created, rendered, touched-up, and uploaded within an hour. I've got about 300 hours in SFM, but I've got about the same on YouTube, Facepunch, and other resources stepping my game up.
I can get overly proud of my work at times, but I remember what I started with. I got into SFM to test loadouts, but I figured out quickly that it wasn't as straightforward as that. Materials need fixing, models need fixing, focal distance and angle need to vary. No poster should ever come out the same as another unless that's exactly what the customer wants. Most of the time, you have free reign, but occasionally, you'll get a customer who has a specific idea in mind and leaves no room for your own creativity. It may be disappointing to not be able to put your own flair on it, but it's the customer that will be enjoying the poster for a while, not you.
There's a lot of specialties in SFM. It's not about having more customers than anyone else doing SFM. It's about being the best resource you can be for what the individual customer is looking for.
I'm glad you're proud of your work, but don't let your pride get out of control. Generally speaking, customers will come back for more if you make them the priority. We all have our own style and "services." We don't need to withhold certain things to give ourselves an advantage. Keep that in mind and the good work going. :)