Don't let others discourage you. They're only mean at the start:P
If you want to make a faction, do it, but it takes a long way. The most successful factions are those who follow an in game equivalent of it's faction to the fullest and are appreciated by the community the most. No one got mad when I've decided to create one character and roleplay whole Synth Foods corporation. These were the times...
Anyway, if it's a brand new idea, which it is, you will need to prove yourselves to the community. How? Roleplay well. Make your story believable, have a preset opinion on every other faction and how you'd interact, spam people with roleplay and never loose your cool. Good luck. There are never too many good Outcasts, if you do things right.