I think Ritchie would not be interested in a reunion also. He and Coverdale have a mutual hatred. Many of Ritchie's ex-band mates do. Ronnie James Dio wrote 'Rainbow In the Dark' about Ritchie. I hear he's hard to work with. ;-)
Burn is one of my favorites also. I am also a big fan of Stormbringer. And the comeback album, Perfect Strangers. But all of their albums have great music on them.
There was one weird one though, with Joe Lynn Turner (the singer from Rainbow at the time). The music was Purple, but the vocals weren't. Even Ian Paice said it was a bad fit. Turner was trying to imitate the Purple style with screaming and it just didn't seem to work. I am a big fan of his talent and delivery (I saw Rainbow live) but could not adjust to him fronting Deep Purple.
There's a lot of great material on the Purple albums to choose from. And tonight I will. After we did the Rush thing a couple of months ago, I did a Rush marathon for a few nights. It was nice to hear them again, since I don't play as much music as I used to. I think old age is catching up to me, but tonight Deep Purple will rock again! :-)