ummm,
How about turning the whole thing on its head, drawing up what features you need and take it from there. Otherwise you face a barrage of recommendations from within a saturated, visciously competitive market where there is no such thing as the 'best.'
If I was predominantly shooting the subjects you mention my list would go something like this:
Instant start up.
Fast memory architecture for writing to media. 3 seconds is the average in consumer line models - an eternity unless a burst mode is offered as well.
Avoid consumer level wide angle offerings - still too many optical compromises at the 28mm equivalent. Consider only if interiors or up close work are vital to you.
Screw filter ring. Lot's of sky so get easy increase in quality and lens protection with permanent UV and occasional polariser use.
For maximum output quality support of RAW format would be important - everything else (Pictbridge Etc) is a gimmick.
Cheap, easy battery replacement whether dedicated unit or standard cells for cold weather/intensive shooting.
Auto modes offering shutter priority and full manual control. White balance is always an added blessing.
When you've drawn up the things important to you and prioritised them it's time to hit the more geeky digital imaging sites. Strange people will have done the hard slog for you and you'll find it remarkably easy to discount the vast majority of the cameras in your price range.
Please note that in 8+ years of running the site I've never mentioned by name any of the cameras I use. I have used CCD based digital imaging since 1974 and storage was on 1.5 inch magnetic tape. Human nature being what it is we tend to overpraise our buying choices and ignore their foibles. What suits me, how I shoot , the size of my hands, my dominant eye, how often I shoot in the portrait axis is different from every other user.
If a 4 megapixel camera ticks the boxes but a compromised 5 mp or greater is cheaper I go for the 'poorer one. Less than one in a hundred of my shots will go beyond 10X8 and a fractal expansion plug in happily caters for the times you want 20X16 or greater output.
However, if you go for radical cropping of your subjects you might well want as many pixels to start with as possible - I'd argue that RAW + fractal enlargement covers me but your answer and needs may be entirely different
Please don't buy what other people tell you to buy. Old, superceded models may not be sexy but they've drifted down the price table offering more of your wish list in the price range you've mentioned. Take your time and think it through - it does pay off in spades.
Regards to all,
Rob