I'd buy an S2 license if I were you. You'll have more cars and tracks to enjoy and it's a different community.
Initially, when you look for online races, you'd probably wonder why not many more races online. Well, most S2 racers belong to teams and race in sponsored league races. Many teams have their own servers and practice in private. Some teams have "team nights" where they race against each other.
All that said, at first sight it may look like there is little or no support for online racing, but if you visit the leagues' websites you can find their racing schedules and may be surprised to see 30 or more drivers in one race.
Some leagues offer multiple races on week ends and all these races are scheduled in their calendars.
As far as this community growing, yes, it is growing. You won't login one day and find everyone gone.
Regards,