RSS Perseverence wasn't bought from the Royal Navy. Sir Lancelot
was already sold of to civilians, in fact, it changed hands twice
before landing in RSN. Prior to RSN, she was actually a floating
casino. 
The 4 current Endurance LPDs (I like to call it rather than LST)
have the cargo capacity approximately to the 6 old County
class.
With the ex-Sir Lancelot, RSN actually has a higher load capacity
than before.
Personally, I hope RSN convert the RSS Perseverence to an
auxillary/replenish ship in support for future green water/blue
water operation, or into a submarine support/rescue vessel. RSN
should then add 1 LPH similar to either the Italian San Giorgio
class, Korean LPX or Japanese Osumi class. This LPH can act as the
command ship for any "Task force" RSN may put up.
Just my 2 cents.