The first two you can live with as long as it isn't too egregious. The last one is a pain in the butt because you have to remove the thermostat to keep it from overheating, that solution may or may not allow you to drive any appreciable distance because those gases have to go somewhere and they blow out the vent into the overflow tank and blow your overflow tank dry so you are constantly topping off the radiator to keep form overheating due to low coolant, and in winter you freeze..
Usually shows up in vehicles with over 150 thou miles.
Just my input (have had two Subaru's, present one has the last named issue...)
Other than that, they're OK... ;-)
My guy replaced the head gasket on the Neon last year. I’ll keep an eye out for it.