is it possible to go straight into the biz scene with just piston hours?
Absolutely. Done some work with a guy who went onto the CJ2 with 300TT at the age of 23, and now flies with a dual TR on the Citation and the Do328jet. Quite some luck involved obviously, but still not impossible.
Is there anything I can do to make me stand out from the crowd?
Get yourself known with the companies. Wash their planes if necessary