Here's a list I came up with:
1. All water-cooled 911s (996, 997, and 991) - those three spawned the most successful racing 911s ever, and in GT Sport, they prove it with gusto.
2. Ferrari LaFerrari - controversial, I know. But tame the wheelspin, and it's actually a track toy.
3. Amuse S2000 GT1 Turbo - same as #2, plus, tune it properly and it can send 911s crying back to their mommies.
4. Ferrari F40 - feels raw, that's for sure. But it corners better than MOST MRs, even with BoP.
5. Aston Martin One-77 - surprisingly good traction for an FR. It's rear heavy weight distribution helps a lot. Benefits greatly from BoP.
6. Aston Martin DB11 - same as No. 5, but with somehow less traction.
7. Mercedes-AMG GTS - another rear heavy FR that has good turn-in.
8. All Homologation Special N Class cars (Gr.B and Gr.3 road cars)
9. Ferrari 458 Italia - a well-balanced MR, though suffers on BoP and slower than an F40 in that aspect.
10. Pagani Huayra - easy to drive and master.
11. Ford GT '17 - same as #10
In general, getting to know every drivetrain's pros and cons will make you get the most from any car.