From my experience too, don't go by what the manual says re globes.  Both times they have been wrong.  Now I will visually check each one  - to make sure..

The LED's produce a very 'sharp' light.  If those globes are facing out towards the blue target - I would go blue.  However , I don't think they would be able to light the mountain area as well.  I've found the #555 & #44's tend to mostly light out from the front - not sides too well (if this makes sense)..

Your river inserts - will be a hyper white colour and really pop.  Sometimes it is trial and error to.  Maybe just order a couple extra (in white) of whats in the mountain and give it a test.  I still think you would need difused white to get the same effect.