I use 2/3-5 wherever it is humanly possible. A fairly high hand position helps me out a good bit. I picked that idea up both from what I seemed to be gravitating towards and from watching Andre Watts play this on YouTube. The last trill, for me, has to be 2/4-5 and it is the one that just gives me fits. The answer there, for now, is to make as much racket with the left hand as possible so the pitiful weak finger flailing on the E and F are pretty much covered up... Look closely at many performers with this last trill/tremolo. Not all of them even hide the fact that they are doing something else altogether. I have seen some where the right hand seems to just tremolo between a cluster of Bb, E and F and the lower E for the thumb.I also think this is one of those things that just takes time and training. I started a slow learning process of the Second about a year ago after having not studied seriously for quite a while. No rush. No huge amounts of mind-bending practice sessions. Just a half hour a day on average. I wanted to learn it in 2 years in a way that is steeped in the score. This section you point out is one of the toughest. The others are the contrary motion 'arpeggios' earlier in the first movement, the D major right hand scales in thirds in the fourth movement and measures 215-231 in movement 2. The latter is not so difficult as it is difficult to play musically. OK... it is hard to play ANY way, but Brahms is asking the pianist to do so MANY things that are really hard to play, and then we have to get it so well under control that it can be done musically.Hope this helps.