Welcome to the Forums! That's a healthy budget for a 5.1 system, and the 805 is a nice receiver with plenty of power for most speakers, but be aware that the Klipsch's you had are very efficient so you may not reach the same level of dynamics you had with them.....but then again it doesn't seem like that matters given the headaches! LOL
This kind of post will yield tons of useless replies filled with subjective opinions about speaker a,b,z and everything in between (see above post already started!)If you were low budget limited, it would be a different story, There's just too much available to go this route without needless confusion. If possible, try and narrow the field a bit with some useful information and here's a few tips.
With a 5.1 system using a sub, no need for the added cost of large floorstanding speakers. The bass these produce by employing the larger cabinets and extra drivers will be wasted as it will be redirected to the subwoofer by the AVR.....which is much better suited to Low Frequency reproduction.
Center channels lock the dialogue to the screen and need to be able to hold their own against the left and right mains. Todays crop of compromise by design center channels often result in poor imaging and off axis response, where listeners to the left and right straining to hear dialogue. Be extremely carefull in your choices here. 3 way center channels using an midrange tweeter vertical alignment will perform better, and only a few mfgrs are producing this type.
Expect 25-30% of your budget for a sub. Cheap subs are a dime a dozen. You'll need something that can cross over smoothly to the main speakers as well as produce clean undistorted bass to 20hz for the full HT experience. If your spending $3k, you might as well get the most from it. Internet brands are a great deal, but sometimes the high shipping costs outweigh the savings of a commercial cash and carry deal. Explore the options and look for free shipping where possible.
The economy is in a free-fall and there's some awesome deals available on some great gear, but be carefull something that's too good to be true often isn't and with a $3k budget, price shopping should play it's fare share and not the driving force of your decisions. Find a balance between quality and value. It's out there.
I'd start by choosing the Left,right and Center speaker first based on available placement options, quality, appearance and value...in that order.
Look for applicable surrounds based on placement limitations such as behind the listener, to the sides, high mounted and the like. Sometimes dipole/bipole surrounds are the best option considering your intended placement. They make the HT surround tracks convincing instead of hoakey extra speakers that are easily locatable and directional in nature.
I know this is a bit of info to process, so i hope i've helped and not complicated things. In truth you really can't just thow $$$ at a speaker system and expect great results. You've taken the right step by coming here in the first place, so continue the trend and avoid the SpeakerA over SpeakerB thing..it's such a waste of time IMO.