Bushings. Bushings. Bushings. All of them. People underestimate how worn and even non-existent bushings can get in 60,000 miles. If your suspension bushings are done, the shocks and springs will wear out quicker, the wheels won't keep their alignment the same - which is bad news for both handling and even tyre wear. Don't forget engine mounts, exhaust bushings, sway bar bushings and especially window guide bushings - there's more bushings on the car than you'd think....
Flyin' Miata sells an "Engine Rebuild" kit; all of the consumables included. All OEM parts or better. Timing belt, gaskets, thermostat, o-ring etc - but is pricey if you don't need ALL of it.
Depending on the funds available, new wheel hubs; they'll make the car feel tighter. FM offer OEM + Blueprinted ones for racing applications. Depends if you have the funds for that, but I doubt you'd ever need new ones again.
Changing fluids from the radiator, engine oil, gearbox and shifter oil, diff oil. It might be worth checking what state the diff itself is in too, most last roughly 60k miles, mine began to shown signs of wear at 65-70k.
Almost everything on the car will wear out between 60-100k miles, some may hold out better than others though. My only other bit of advice would be clean, like a maniac
dismantle and clean up everything.