In my experience, the main thing that distinguishes gas stoves is how precise the flame control is and how much heat you can throw off on at least one burner. (And, I guess, the flame pattern although given decently thick-bottomed pans it doesn't really matter much.)

But in general, a gas stove is a ring of flame. There's not much to it. You need enough flame and you need to be able to control it. If you have those two things, an old stovetop is fine.

Ovens are more complicated and I'm not generally a fan of gas ovens.