I would have to agree with most of the others the FT-450 would be a perfect fit for you just for :
It is a desk top radio
It is a newer design
Plus HF and 6m
I tend to avoid a shack in box combining all your radios together because if one goes down you have nothing. I take it you must have a 2m rig now use it and the rest of your money use for a HF radio only.
I do have several Icom 7000's and they are great radios they are a much better radio than the FT-857 and I'm a Yaesu man but the cost is more than you want to spend. I use one mobile and the other in a (Go KIT) and for field day.
But one thing to remember antennas, antennas, antennas and good coax. You can have the greatest radio in the world if not connected to a good antenna a cheap radio with a great antenna will out preform it every time.
Good luck and welcome to the world of HF real radio :-)
73 de Fred N0AZZ
The License is Only Your Starting Point in Radio!
MVDX/CC of SW MO., DX Hogs, OARS, NARC, NCDXF
ARRL member, ARRL and W5YI VE
DX the thrill of the chase
""D-STAR making use of the 2/ 440m repeaters for real world Digital Voice usage around town and around the world""
" Not one of us can do what all of us can do " ** Max Lucado