Portraits, Landscapes, Children, Light-weight, Low-cost & possibly able to handle low light photography as that may interest you. I think that was your shopping list ?
Ken made some good suggestions above - as did one or two others - mentioning that maybe a more advanced digicam was what you may need.
Let me offer another suggestion that I've been hands-on with: Olympus SP550UZ
US$450 - 499
4.3" x 3.1" x 3.1" (should fit your hands well)
28 - 504mm (x18 and f2.8 - 4.5 means great for your landscape photography & portraits. Add one of two conversion lens to widen or lengthen (up to 850mm) :?
365g - Lightweight
ca 600 shot on 2700mAh (class leading)
AF Assist lamp (low-light help)
IS (Image Stabilisation) (low light help)
10 x ISO settings covering 50 thru 5000 (yes really ! At 5000 it drops to 3 MP and probably the noise will obscur the photo - still it's there to be used in an emergency :O
20 different image resolutions (inc. 3 Raw plus jpeg+raw) (+ in-camera editing of Jpeg & Raw)
2.5" LCD and EVF - both auto adjusting
Full Manual Mode - bulb to 8 mins (however fastest shutter is only 1/2000)
pre-capture (5 frames) and up to 7 fps burst rate for 15 frames (really ! However that's at a lower resolution of 3 mp - still great for the children's & dog's action photos)/ It actually does 15fps at 1.2 MP but not so great for prints although OK for emailing.
AF Predict (good for moving children)
Multiple WB modes (inc. custom) and also WB compensation (adjust red / blue)
20+ scene modes (inc. 2 x underwater)
Underwater housing available
Movie mode (30fps 640 x 480)
and so on and so on, there are many more features.
Obviously none of the features of the 550 on their own will match the equivilant feature on a DSLR, but it is such a feature packed package, that covers all your bases, so it may be just what you are looking for.