When making perfume I always used Cyclomethicone as the carrier, added a little light oil, and fragrance or e/o, never had a problem with the fragrance not lasting long. Of course it does depend on what fragrance you use.
I don't live far from them and can actually sniff the fragrances out of bottle while there, but to tell you the truth I never bought any fragrances from them because the all smell weird, the have some sort of chemical smell to them and that is why I have never purchases f/o's from them.
Also depending on what wax you are using, you could try wicking up. I've used square containers before, and had a circular melt pool, but over time the little bit that was still hung up eventually melted.