Having said that, go with the job that you want. if you want to take the job offer you have now and still keep looking, go for it. There is no guarantee the "big time" job you are looking for will open up or you will get it if you apply.
This is about you and where you will be happy teaching. You are the one who has to go to that job every day. Not anyone else who offers you advice on this board.
There are school contract rules for a reason. Use them to your benefit yourself if it helps you to be somewhere that is a better fit for you.