I don't think there is any one car that can do both oval and road course racing perfectly if the club is super competitive. I know when I used to race oval in a very fun, medium competitive situation running 1/10 scale I just ran a standard road course setup, in other words for our small track that was flat you were lapping traffic so quickly that not having a purpose built oval car at that time you were not hurt too much. I also ran much more road course and it didn't make sense for me to buy a oval car as little as I ran it, but when I did I could still do pretty well. If your club is the same then maybe you could buy one car and just have fun with it.
The other option is to buy a road car and a oval chassis plate or vice versa. That would require swapping chassis and radio gear layouts but it adds more cost.
If your interested I am selling some used 1/12th scales that I no longer need. The car is out of production now and actually for a few years but I have basically 3 cars and I can sell them pretty cheap to you. The spares could keep you running for quite some time. Please PM me and we can discuss further.
Team ORCA / ORCA USA / Pro Spec
Serpent America / Team Serpent S411 ERYX / On Point Racing OP12C, S120 / Xceed Products
Hangar 30 / Seattle RC Racers
Fasttrax Racing Series / NORA On Road Series