The 948's, with their hideous impedance low point of 2.5 ohm compounded by some phase angle, aren't easy to drive. The Kanta and all the Sopra's are easier to drive than the 948's. The thing I like about the 936's is they're not the most politely voiced speakers out there. They have a smooth, meaty, physicality to the sound from top to bottom that I think a lot of other speakers are voiced to avoid in the interest of sounding more polite. They attack from all angles when it's called for and they lay back and chill when it's not.
As far as an update to the 900 series, I'm not sure what they'd change. Maybe the TMD driver from the Kanta?