NO.
First of all, regarding switching to Ashkenazi minhagim, Rav Ovadia forbids it. Ashkenazim are allowed to replace their Minhagim with the Sephardic Minhag, not the other way around. Sorry, but that’s how it is; you're stuck a Sephardi.
Now, you are also ENTIRELY forbidden from adopting an Ashkenazi pronunciation over a Sephardi one. Because you are capable of pronouncing the Hebrew letters distinctly, pronouncing them differently would be considered speaking nonsense. In fact, many Rabbis, both Ashkenazi and Sephardi, have ruled that everyone should adopt distinct pronunciations of letters wherever possible (although that ruling is obviously not widely accepted). There are tens of Rabbinical sources, many of them famous, one of the most persuading being the Yavetz. He was always extremely critical of his own congregation’s Hebrew pronunciation, writing about “our shame” and even “constant transgression” that he and his community couldn’t pronounce Hebrew correctly. If he knew the correct pronunciations, he obviously would have tried adopting them.
You already know good pronunciation. Your tradition from your parents is a privilege. Don’t allow yourself to forget it. Having an old Mesorah is valuable.
Other sources include: Rav Yihya Yishai Hallewi’s "Introduction to Tephillath Kol Peh", Rav Ovadia Hadaya’s Yaskil Avdi volume II chapter 13, Rav Yehiel Weinberg’s Sidrei Esh vol. II chapter 5, and Ben Ish Hai’s Rav Pealim vol. II response 25.