I've been around both NJMP tracks at speed and paced. The Lemons 240s seemed to like Lightning last year. Good tires, lightness, grip, lower center of gravity, stiffer chassis and suspension and fresh brakes is what you want. And power.
Gut the interior, add chassis braces, get good tires (Hankook Ventus RS-3s are good for cheap), add IPD springs and sways with Bilstein HD shocks and any Volvo would be a fun little weekend track toy for not too much money. As for brakes, stock Volvo rotors with Hawk pads are great. I autocross and drag race my 960 from time to time and my biggest pitfall is tires.
As for your question about Volvo strong points on track... Not many. The chassis aren't horribly stiff, they're mostly all under powered, they're mostly all over 3,000 pounds and most of them have long wheel bases. Not great for road racing. Strong point I think would be brakes.
I still love driving on the track in my Volvo and going fast. It's just a bit harder to make a Volvo go fast than it is a comparable BMW.