Based on your requirements, if you do not mind getting a 2nd hand body and lens, the Canon 40D + 17-55mm f/2.8 will suit you for a start. Though this is a 3 years old model but the image quality that it is able to produce is good. Combo it with a fast and good glass like EFS 17-55mm f/2.8, you should be able to cover standard group shots to portrait shots of friends and pets .
40D + 17-55 f/2.8 should cost about $1800 to $2000. As such, you should have the remaining 1k for a Speedlite 430 EX-II, 30L DigiCab Dry cabinet, camera bag, normal tripod, remote trigger etc.
If you are aiming for a new body, you can go for 60D body only. Then, go to BnS and get a 2nd hand 17-55mm f/2.8. This combo will cost you about $2600. Thereafter, your remaining $400 will only be able to cater for the Dry Cabinet and a standard tripod, probably a filter or wired remote trigger at most.
You have 550 left to buy filters, tripod, bag, flash, whatsoever.
I think this combo will cover most of the things that you want to shoot with great IQ and the for the body, you can upgrade to 50D, 60D whenever you want. Just my 3 cents. Hope it helps.