I agree. Your current equipment will be more than enough to get you started again until you feel like you can handle your RS4. You will need to buy new batteries most likely and NiMH stick packs are still available at around $35 or less.
Once you feel like you've reached the full potential of your current chassis or electronics then an upgrade would be your next step.
6 years ago I was racing and the hot setup at the time was Novak TC Cyclone esc with matched 3300mah NiMH batteries and Epic 27t brushed motors. Now the hot setup is Tekin RS/RS Pro, Castle Creations Mamba Max combos and 40c/50c 5000mah lipos with 17.5t or less brushless motors.
Equipment back then wasn't a small fortune, could pick up a good competitive esc for $90-$150 and motors were $35-$50 and batteries at most were $90 (for good hand picked matched 6cell packs). Now you're looking at $200-$275 for a brushless esc and motor combo, $80+ for a spare motor, $80-$130 for a good competitive ROAR approved battery.
Prices have went up because of the advancements of RC technology, definately a new world of RC you are coming back to.
You can find better prices with other equipment I was just using Castle Creations and Tekin as examples, Novak still makes good affordable equipment.