Difference between the assessee and non assessee registratio

good morning ,

i have registered as non assessee in service tax, and im paying the tax amount from past 2 years but unable to file the return. got to know from aces department that i cant file the service tax returns as im a non assessee.im ok with that!..........but what i want know is

1) will there be any problem in future if ill not file the returns? 

2) my gross income is more than 10lakhs, do i need to convert to assessee from non assesse to file returns?

please do help me im cunfused