Back in the day you got Götterdämmerung on six LPs. The Perm Figaro has opened out some cuts, so all the arias for secondary characters are there, but I don't think he has managed to bloat it to Wagnerian proportions. It is on three CDs.
From the late 1970s on, most (studio) recordings of Figaro contain the 2nd character arias, and f.i. the Solti recording was on 4 LPs.
Maybe the modern (higher quality) pressing has caused the larger amount of discs, with a.o. deeper and broader grooves, which leads to a smaller amount of music on each LP side. But I'm not sure, because I ain't no HiFi technician.
About the critics: not only Kermes is 'whispering', there is much more voice acting around, also by the male characters. And yes, the continuo is made very important, but Currentzis is explaining most of this in the booklet.
Really, if the (professional?) critics have read this booklet, then I want to be a professional critic, too. Very easy moneymaking.
Examples of such 'professional' (?) criticism:
Booklet: we opted for another pitch, for reasons this and that.
Critic: OMG, it sounds as if they're playing in another pitch!
Booklet: from sources we understood that the continuo was a leading factor in operas during the composer's lifetime.
Critic: OMG, the fortepiano is very prominent!
Booklet: we know that the composer also made very attractive ornamentations for other composer's operas, and from that we suggested that such decoration was common in his lifetime.
Critic: OMG, all those ornamentations!
I like Giulini, Böhm, Von Karajan, Solti, Gardiner, Mackerras, Jacobs and Currentzis in this opera.
And I'm quite convinced that all these conductors were/are each quite convinced that they offer the best solution. Currentzis isn't an exception here. Yes, in the story Susanna is the one in control (mostly), but for the musical production, in the end the conductor has to take control. And Currentzis apparently did. With many good and some less good results, but as a whole this recording is a recommended choice to add to one's Figaro collection.
Just my tuppence worth, of course.