Hi Ed
OK, the muddy reverb has passed away, nice.
Maybe you did the jobs "shift to the right" and "shift to the left" a bit too good, now. [;)]
But as always: It's a matter of taste.
The whooshing sound of the violin can come from using the X-velocity function.
While crossing from one into the other layer we get phasing effects. It sounds like we would have two violins - a small ensemble.
We don't recognize this effect with ensemble articulations but unfortunately with solo instruments very well.
And yes, specially with the violin and its sharp sound it can sound very "phasy".
So that could be the reason... Another one I don't see at the moment.
If it is so: Use the real dynamic diminuendos/crescendos of the solo violin (unfortunately only available with the full library).
These are probably bad news. Sorry.
Tip: Use the articulation "détaché short" or "staccato" for the short tones within your piece. The legato attack is too "weak" for short notes.
About the concert hall-preset of Logic's reverb: I don't own Logic any more since version 5.5. (WIN-users bye bye).
But I can't believe that all the effects of the current Logic version don't come with some factory presets.
Click on all the "switches" within (the head?) of the Reverb for searching them.
When you have found them then choose a similar to "concert hall".
I remeber a preset with the "Platinumverb" called "small hall".
Hope that helped a bit.
Beat