firstly ditch the cheap ass tyres. they are your ONLY contact with the road and make a HUGE difference to a cars handling...FACT! oh dont go and put pirrelli p6000 on, they are wank and have been nick named pirrelli ditch finders. get some hancook v12 or s1, very good tyres.
secondly, go lighter with the throttle. cars were first built rwd, the original mini was the first to be fwd. it just takes a bit of time to get used to driving rwd cars. gentle and smoothness is key to driving safely regardless of the car.