Just wanted to post an update.
The Gummi Pflege I tried did seem to plump and rejuvenate the drying areas of rubber a little, but I didn't feel it was a significant enough difference to warrant buying it in addition to the Autoglym. It did a great job on the seals of my sunroof, though - no more drips on my head!

I've continued to give a very light application of Autoglym to my crew every couple of weeks or so, but I've not felt the need to give them another 'bath' in it as I did with the first application. I have applied it a little more liberally in armpit areas and under the chin, where there is a tendency to wear.
I have now done blue Belle the RB as well. I don't know if it was because the skin was newer, or if the RB skin is different, but I found the Autoglym seemed to take longer to 'sink in' with Belle, and the slightly slippery, damp feeling took longer to wear off. It did wear off, though, and it cleaned her up a treat. I notice the blue paint shows up any surface dirt a lot more than the green does!
