Brahms - music for violin
What do you think makes Brahms's violin compositions so challenging for the right hand?
I don't think Brahms is as hard for the right hand as Mozart is.
Vivaldi I suppose.
The fact that you don't play like James Barton?
Which Brahms compositions are we talking about? I don't find his violin sonatas (2 and 3 at any rate) particularly challenging for the right hand (at least, certainly not any more than its contemporary sonatas). If you play enough solo Bach (or, as Mary Ellen noted, Mozart concertos), I believe you will feel the same.
For right hand? There are challenges maintaining a good sostenuto, there are challenges shaping and lengthening phrases. But I agree, for bow technique Mozart, unaccompanied Bach and Beethoven are probably more demanding.