Look at the space you gain by covering your pool with Deckover!
Consider the costs and maintenance headache. If the pool actually gets used, then re-plaster.
If it's not being used, then consider Deckover!
If you re-plaster, consider that...
Sometimes, the swimming pool contractor may exaggerate the efficiency or effectiveness of the equipment.
Remember that when you re-plaster, the money pit goes on.
Has the cost of any of these items gone up in your area?
What will those prices be 5 years from now?
Is it difficult to find someone to take care of it while you are gone?
Not only do the costs continue, but so does the headache.