The best racing faction I have been part of on SAMP was called 21s and it was pretty much just a group of friends that had a passion for cars. So it was that kind of semi legal RP in which the members were enjoying their passion and were trying to make a good income.
Things that the crew were against were putting others in danger, so during races, passengers were not allowed, and getting in pursuit with the police was discouraged due to the safety hazards. Although, sometimes they just happen, but the most important thing then was that, the members would try to make the chase as safe as possible, for example avoiding populated areas or hitting cop cars.
Another thing was that weapons were not allowed at all, members would not be welcome on an in character basis if they put their hands on a gun. If a pursuit ended badly, the one unwritten rule was: it is over, just give up and don't make a scene. So the members did not really mind if they themselves got hurt, but they cared a lot for others.
Other activities included going to clubs, bars, managing garages and so on, as the characters were all youngsters, up to like 35 years old. So I would like to see that sort of crew around, one that promotes having fun. The cars are really irrelevant but trust me, using Jesters, Elegies and Sultans is all part of the fun. There is no need to go down to Feltzers, since tuners are affordable. Going up to supercars should be avoided as they are less affordable.
All in all, focus on fun rather than thinking that you should copy some real life stereotype. Make your characters, develop them with your imagination, that'll be a lot more fun than trying to recreate Billy who is poor and starts racing in a Glendale and has some boring generic life and roleplay.
