As a biased Jeep Wrangler owner I would recommend the Jeep Wrangler Unlimited. The only box it doesn't tick is your desire for a V8. But being a tall vehicle it easy to work on, can be optioned as much as you want regardless of transmission, Jeep's reliability, strike that, FCAs reliability isn't the best, but the Wranglers seem to have less issues than the rest of the Jeep stable (primarily due to the transmission).
Wrangler's also come with a decently powered, and a great engine, pentastar v6. Cost of parts for Wranglers are relatively cheap, especially because of all of them that are out there as well as an extremely strong aftermarket. Plus they have some of the best resale values out there. Either top type gives you open air abilities, the hard top with the Freedom Panels, and the soft top going all the way down or even just in sun rider. A four door gives ample room in the back seat with the fun of a wrangler still. Oh and the door come off if you feel the need to go full convertible. If safety is an issue opt for the optional Side-Impact airbags, they're a $500 option but in a wrangler worth every penny. Did I mention the piece of mind of a lifetime factory warranty if you wanted to?
You lose the speed and throatiness of a nice V8, but what you gain is a vehicle that can go anywhere and do anything and be a convertible while doing it, just don't forget to wave.
HOWEVER, the 2018 Wrangler will be debuting most likely around the time you'll be fully looking. It may not be the same vehicle it is now come your time to buy so it may not be a great option.
I agree with those other guys and love the Dodge Challanger. I'm a huge fan of the 492 Shaker (40k option) type but with the engine choices and transmission choices (A/M), its not a bad car and the back seat is liveable. It doesn't drop it's top but it does have the option of getting a sun roof if you still want the wind through the hair.
Unfortunately nothing else really fits your bill with out wavering into a different manufacturer or taking on other compromise such as engine, seating, etc.
I'll just loosely suggest a Chevy SS. Yea, I know, no GM, and it's def not a convertible. But it is a v8, it is a sedan, it has a manual, its RWD, comes with a sunroof (I know not a convertible but at least you can still get that wind).
I've had a Wrangler for 2 years now with a 6speed and haven't had any issues with it. Transmission isn't terrible, engine is plenty powerful enough, going topless is the highlight of my day, and it does great in the winter as well.