Is Starting a Freelance Company is Good Business?

Hello!

I'm doing Graphics Design/Multimedia freelancing from last 2 years at sites elance.com & guru.com
i always take it as a part time job... i'm doing it from home! but from last few months i'm earning more then from my full time job!
So i thinking to leave my full time job & make my freelancing as full time!
my more then clients giving their all projects to me but i need to say them No! bcoz i can only complete 4-5 projects per day! i want to take all projects i have getting so i can earn more..~

So yesterday i thought if i should start a freelance company & hire people, give them salary then i can earn more

if somebody doing any business like this then please suggest is it good profitable business ??? for life & feature