Revise the customs union. This is all that Turkiye currently seeks from the EU. Disregard the visa liberalisation; it pales in comparison to the significance of free trade. I live in Germany, I find myself forced to purchase Italian, Spanish or Greek watermelons, as they are half the price of Turkish ones. Additionally, many are unaware that Turkey serves as a significant hub for IT services. Currently, these services, along with digital trade and professional services, are not included in the FTA.
The Europeans are prepared to revise the customs union; however, they remain uncertain about what specific concessions to seek from Ankara in exchange. Once trade between the EU and Turkey is unrestricted, Brussels will have limited influence to force Turkey into any decision they deem necessary for themselves.