Most Renderosity users are not the target market for C4D, LW, Maya etc. Those packages are worth what they charge because the do some things incredibly important in a cinematic, animation work flow - but only if you are working in that space. 

Carrara's market is both the Pro and Amateur that want many of the features of the larger packages but don't need the integration, more sophisticated feature/control sets and so on. I use Carrara very regularly in my studio because it is an excellent choice and is a heck-of-a-deal that does many things very, very well. But it's also not in the same league as the cinematic applications either - and it's never claimed to be. 

The artistic capability of a pencil is always determined by the user. It's always more important to actually learn the tool than by another one hoping it does the job.  ;-)

Just the crazed ravings of a lunatic madman...