Cap d'es Falco is amazing - but it's isolated and out on its own. The Hostal la Torre is very close to San An / Mambo - but a 5mn taxi ride rather than a walk and there's nothing else really in the immediate vicinity in terms of other things happening. If you go further along from Mambo round the prom you get to Es Calo d'es Moro, which is where I usually stay round there - 5-10 minute walk from the Mambo chaos but quieter - you won't be alone but far fewer people and usually a spot available for a private moment nearby. Problem is you need to go further round the coast (preferably by car) to get to a decent restaurant at La Torre !
Do you intend to pop the question before, during or looking over the Sunset, and before/after dinner ? Sounds daft but it does kind of make a difference to where might be ideal. If the restaurant itself is enough of a decoy, and it doesn't matter if it's on its own, then the options are greater. The s'illa d'es Bosc restaurant at Cala Conta is nice btw .. not so overwhelmingly fancy as to rouse suspicions and food is decent enough. It's also close enough to Sunset Ashram where there will be loads of people (so everything looking 'normal') and there are miles of cliffs immediately adjacent to walk off to for a private moment right on the doorstep.
http://www.silladesbosc.com/
The place is upmarket but laid back, and they're extremely helpful - called out a tow truck for my hire car and sorted everything after I went swimming between aperitif and my lunch being prepared ... with the key in my pocket
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