Take everything you were issued. When you get to sultan you’ll be issued more kit. When you join a ship you’ll get even more. How you store it with the space allocated will be up to you. If your phase 2 is anything like mine was, you will still get kit musters if it’s thought they’re required.
You take all your kit with you every time you go on draft and you will get kit musters in Phase 2, and the lockers are bigger, but not much.
Where civvy clothing is concerned, if you can't carry it, don't take it. When I was a Phase 2 DO I lost count of how many came to see me complaining they had too much gear to carry and expecting pusser to pay for it to be sent on, they either had to ditch it (not issued kit) or sort it themselves.
Just a word of advice which you can ignore if you wish.
Seems rather remiss of the discharging or receiving unit not to brief those going on draft of the standard requirement to take all issued kit upon joining.
Likewise, when joining your first ship, a swept up Divisional Officer will send you a joining letter outlining your new job, a rough outline of the ship's programme and any additional kit beyond that already issued which maybe required (ie Tropics, DPM, etc)