Touring car has to be a Vaterra V100, had mine for 3 years nearly, once I upgraded the drivetrain to the Hälix metal gears and full camber adjustment, spot on. Ive let competition drifters try it on 7900kv with hard slicks and a gyro, they loved the balance of it.
1:8 buggy was my XTM XT2E, 2650kv on 6s, hit a tree, £8 worth of damage. Was just a brick solid animal but fun to drive, again, had mine for years and it never went wrong.
1:10 Rally as ive only had an FTX Hooligan, ace little car for the money, quick on 5200kv but easy to handle
1:8 truck, Hobao Hyper MT, only MT ive owned but its a bit of fun as I'm used to handling, this thing is bonkers on 6s.
will always love the Tamiya TT01 for its reliable chassis and cheap parts but more for its versatility. Got a few more but this is a good baseline.