Probably not that weird, but mixed spice goes very well on melon (particularly canteloupe). Also goes well if you sprinkle it on pears (especially those lovely Golden Taylor ones that are only in season for a very limited time), chopped into chunks and put in the microwave for a minute or so.

Sugar - I would never consider adding to ripe fruit. Green mango, maybe, but sugar on strawberries?

Lemon juice can be nice on Russets - they have a lovely, soft, sweet flavour, but the late season ones can be a bit too sweet.