I know Malta well and i wouldn't say it was deprived at all. In fact i would say the Maltese have a good level of living standards.
For a couple, I think it is great especially if you want to do other things rather than the beach everyday.
Assuming you want more than a beach area.
Here are my tips
- care hire is cheap, Maltese driver mad, parking can be tough, but we always hire a care. Bolt and Uber cheap and plentiful
- Food- you can find cheaper local restaurants to more expensive chic ones. Lots of choice. Not as cheap as it once was.
Good places to stay
Valetta - I would love to stay in one of the boutique hotels. Very central buses to everywhere, probably best if you don't want to get a car. If I had all the money in the world I would like to stay at the Phenicia.
Sliema - up market area, make sure your hotel has a carpark if you are hiring a car.
St. Julian's - another nice area, the Hilton is there but also look at the Corinthina hotels.
I would not choose to stay north of the Island, very nice for a visit.
Places to see
Mdina
Go to Gozo for a day
Swim off the rocks at St Peter's Pool (Marsaxlokk, you need a car or taxi)
Eat harbourside in Marsaxlokk.
Valetta is beautiful by day and night, enjoy pastizzi and coffee in the morning. Lots of historical things to see in Valetta.
Dhingi Cliffs
Vittoriosa, visit the church, walk round the little square and have lunch over looking the yacht marina. Take the boat back to Valetta.
Just take the car and see where it takes you.
It is a loud, busy and dusty island, don't expect pristine beaches, most swimming if off the rocks. September is perfect, sea will be lovely and warm.