@OP - is your turntable a TT16 or 15 as I cannot find any references to a Marantz TT16 - perhaps you could post a picture which would allow a more precise response to be given.
Answering generically - yes, a better turntable and arm can make a big difference. The Linn philosophy was taken to extremes, with people running LP12s with Ittok arms and cheap K9 cartridges and getting pretty poor sound from a large investment. However, with due regard to upgrading a system in a balanced way, better turntables do make a difference - more resolution, better pitch stability, more bass extension, blacker backgrounds, better control of surface noise etc.