Try for a 60 day e visa next time and extend for 30 days, you get 90 days total. Fly out of the country for a few days then enter on a visa exemption and extend for 30 days.
But as said it really depends on the officer. If they see this happening to often you may be asked questions.
I think the best way is to work out how long you want to stay in a year and apply for the right visa for that time.
I know there is also a multi entry visa valid for 6 months. Might be worth looking into.