Your better track cars are going to be the Miata, FRS/BRZ/86, and Corvette, all of which come up a bit short in the practicality dep't.
The Challenger is in the right price range and has practicality in spades, but it's the wrong car. You'll see one from time to time (maybe even a Charger), but my money's on track day driving not being very high on the list of reasons those people would have had for buying it . . . if it made the list at all. Most hemis end up running in straight lines.
I can admit not knowing a whole lot about what imports would be available and suitable at this price point. Saw a Q50 out there once, which might mean that somewhere somebody will probably take most anything out.
$70K is a good bit out of my budget.
'08 GT coupe, 5M, wheels, tires, pads, fluid, a few suspension mods . . . still almost stock height
'19 WRX, 6M (hers)
'01 Maxima 20AE, 5M (spare, winter driver)