Gmac, do not get disheartened. Yes there is inconsistency just as in real golf. Just go to the driving range in real life and hit a bucket of balls using the same club and swing - you will get variation - even the pros do. Add to that wind gusts, swirling winds, protected areas from wind etc. and you will find that it is not drastically different to on here.
Finally you are also using low end clubs - they are neither very precise nor forgiving.
All that said, the top players have worked out the algorithms to score very well. But they have played many thousands of rounds and taken notes to do so.
My advice is to set your own goals and above all, have fun.