Don't want to be stating the obvious but burning petrol is normal, it's a petrol engine. If you mean it's running rich it depends how rich and may well be just the colder weather. All of which is irrelevant - your problem here is your burning oil (not good) no amount of servicing will fix this, your valve stem seals need to be changed.
Leaving the valve stem seals alone will only mean the problem will get worse with time, it means you get carbon build up around the valve guides and more oil being used which consequently means more blue smoke, it means you need to keep checking and topping up the oil, which means more money but yes it is drive able.
It's a inline 4 petrol engine as was your nova, if you have done a valve stem seal on that then you will be 100% confident doing it on a golf inline 4
I don't know what a "valve block" is