We talked about this - I stumbled into what you're describing by buying my E36 318: lightweight, 50/50 chassis, RWD, 6500rpm-redline highway burner that is simple-yet-robust, with a wide aftermarket of available parts.
Look at E30/E36 318 'verts...you'll have legit seating for 4 adults plus a trunk PLUS air-con and power accessories for under $5k.
If you search enough, there are E46 323/325/328/330's, but IMO they got a little too fat and laden with electronics for their own good. Even with that being said, you've got an OBDII modern car that's still cheaper than the classics, with a fleeting semblance of soul leftover.