Land drones too. So the justification for NS becomes more and more flimsy.
If all you want is just some patriotic coming of age national ritual, then pay NS slaves wages commensurate with that which is paid to regulars. Make it a mandatory one-year thing, with a choice to extend contract for one year up till a maximum of three years. Contract extension benefits = tax breaks, pay increase, education subsidy, CPF bonus; real tangible perks, not crap like SAFRA membership, NS credits that can only be used at certain retailers etc.