For budget shooter, I think it's good to go for D90. As the kit Lens is 18-105 VR.
So it actually covers a pretty good range. Maybe just add a 50mm prime lens for portrait shots.
So pricewise is quite affordable too.
Whereas for 50D, if you take the 18-55 kit. The range is actually pretty short.
If you take the 17-85, many said the image sharper & clarity not good.
So it depends a lot on your budget & which system feels more comfortable in your hands.
Happy shooting when you made up ur mind.