The halves 'logjam' is already working out more or less as could have been predicted. It was unlikely that all three of Galvin, Sullivan and Fainu were going to become stars, and Sezer was always going to be a bridge to Luai. If you'd offered me the following in February I'd have bitten your hand off: Sezer a very competent game manager, Galvin a potential star, Sullivan a very big question mark at best, and Fainu still unknown.
The good news is there are plenty of teams absolutely starved for halves so if Sullivan gets squeezed out there's every chance someone will take a punt on him without the Tigers having to carry any freight. As things look right now you'd have your money on next season starting with Luai at 7, Galvin at 6, Fainu most likely 14 and Sezer - if he wants to play on and doesn't get a starting offer elsewhere - in reserve grade and ready to back up.