I agree with the bolded part. Don't forget what you have invested in it and it is known in terms of repairs. If there was a drastic difference in price I would consider it but this isn't enough, I don't think.
If you travel off season or a last minute trip you can save up to 70%. Using a smaller airport or staying somewhere just outside of a city are other ways to save. I plan far in advance and watch the prices. I always get good deals on vacation trips.