Yes, your preamp would be the weak link if you bought a separate phono stage. But will it still sound good enough until you decide to upgrade your preamp? Only you can decide that.
You are caught in the upgrade dilemma: as you upgrade individual components, their performance will always be limited by the weakest link in your system.
You are caught in the upgrade dilemma: as you upgrade individual components, their performance will always be limited by the weakest link in your system.