Well, I'm not so sure that additional keywork is a negative overall. I'm just saying that on MY Yamaha German System clarinet, the additional venting didn't seem to work as intended.
Had I purchased a simpler Yamaha German System clarinet (or another German brand) I may not have had one problem I came across with the YCL 457-20 I bought. That problem was that the intonation-vent-connection to one of the tone-hole rings was of such a nature that if I didn't deliberately ensure the ring was totally depressed when passing over that note, the mechanism failed to close the intonation vent and the whole horn went south. That became annoying time after time. Could it have been corrected by a technician's adjustment. Maybe, but at that point, I was about done with the struggle.
On saxophones, we've become familiar with additional keywork and while I love my vintage saxophones, I admit that my modern ones are better players - the additional keywork that comes with modern saxophones sure hasn't been a hindrance to my playing. Tone-wise, it is more about me than the age of the horn or the presence of additional keywork.
And, to bring up a continuing argument, I don't think the Albert clarinets sound any different than Boehms, although many will disagree. I'd defy anyone to listen to my playing (if they could get through the clinkers) and identify which system I was playing without looking at my clarinet.
So, while I think a plain old Albert (and I own two now, have had more) has a better scale than my new Yamaha, I also think my Buffet Boehm (an RC Prestige from the early 1980's) has a better scale and sounds better (and plays much more easily for me) than all of the Alberts and Oehlers I've owned. DAVE