Very few AVRs will give an honest 100 watts out of all 5 channels simultaneously; certainly not the one you have now. AV preamps are usually more expensive than most AVRs, but a good compromise would be an AVR with preamp outputs; however, you're going to spend a bit more.
When I was recently looking for a used AVR with certain features, here's what I did: I set up an automated search using this string:
receiver -(vintage,sansui,kenwood,technics,nakamichi,fisher,panasonic,shure,satellite,stereo,shortwave, proton,dvd,pyle,extender,tv,kit,kramer,wireless,rockville,tascam,adc,technical,blackbox,kardon, hall,directv,crestron,extron,sonos,fiber,foxconn,teac,radio,optical,motorola,transmitter,adder, samsung,catv,"black box",blonder,audioengine)
This allowed me to rule out all the stuff I knew didn't have what I wanted. Then, as results came up, I'd enter them into a spreadsheet, with the make, model number, and relevant features. If I wasn't sure if that was what I was looking for, I did a little research online. Eventually you get to the point where you know that models above a certain series have certain features, no matter what the generation; that models that were made before a certain year don't have it, etc, etc, and you don't need to keep researching every model that comes up. For example, the Onkyo TX-SR705 has what you need (HDMI switching and preamp outputs) but the 605 and 703 don't (the 704 doesn't seem to be that common, so I didn't know for sure). This means that the TX-SR805 (same generation, one level higher) and the TX-SR706 (next generation, same model level) would also have those features.
However, having said all that, are you sure you need a true 100 watts of power into 5 channels simultaneously? Your current receiver can't deliver that.
