Battle 1 is a tough choice... In sims, I love Monza for F1/Open Wheel and GT racing (especially in AC!), but Sonoma is one of my favourites for Touring car/Historic racing... hmm...
But when it comes down to it, I think I love Monza more. Sonoma is a very technical and exciting track with lots of elevation change, but Monza is great for every opposite reason - it is the road-course equivalent of a Superspeedway, and it requires big balls to go fast. The track also has such a great atmosphere, and the Monza GP every year has a special place in my heart as the first F1 race I attended (and only outside of Australia).
So Monza it is, but only because 50.1% of me prefers Monza, whilst the other 49.9% prefers Sonoma
Bathurst is an easy pick for me. No question. Best race track in the world, even better than the Nordschleife (although how that was knocked out first time is still puzzling to me :/) because of the complete package - low speed 90° corners for overtaking, fast run across the top, high elevation change... and close walls like a street circuit. Plus, I think it has the best chicane in the world (The Chase), which is one of few chicanes in the world that actually improved a circuit IMO. Some of the Monza chicanes are included in this description too - they're necessary for most overtaking at the circuit
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