I got married in October and we went to Lake Garda for five days for honeymoon. It is lovely and I can highly highly recommend it. Probably best if you go early in the spring before the tourist season really gets under way.
You can also take a day trip to Milan for some shopping and to Verona for some more shopping and to look at some the old parts of that city, which is great.
We had a 3 day stay in a gorgeous hotel in the Lake district. The other 2 days were funnily enough spent back in Stockport, where we both worked at the time.
Though the flight is a little longer than you want, I would highly recommend New York a fantastic city. For something a little closer how about Paris, there's so much to do and see there and its easy to do the non-tourist stuff too.
Almost be worth getting married again to go back there! Kayaking up to the bears, getting cut off from the boats by stray male bears, a ride in a float plane which leaked in the rain, eating crab that you helped reel in that morning, the most amazing home made cookies/hash browns/pancakes….
We live in Sardinia so can comment on this. In August it's hot but biking down to Cala Luna and meeting the Mrs who's come on the boat would be pretty cool and you could find a group of hubbies to do it with. You can even rent hardtail bikes from where we live. For photos in August see Cala Luna August Round where we live, the Monte Turri hotel would be a nice posh place to stay. cheers Peter