NOTATIO

Are there general bowing guidelines on when to indicate bowing and when to leave bowing to the conductor and players?

Mostly, don't indicate bowing unless either you are a very competent and experienced string player yourself, or you require a special effect such as consecutive heavy down-bow accents. Here in the UK, the section principals usually mark the bowing in the parts before the first rehearsal, assuming they get the parts in time. Chamber players will usually discuss bowing during rehearsal.

Take it from a long-time orchestral librarian: Never mark bowings in the part - even if you are a string player. Every concertmaster and/or conductor has their own ideas about how to achieve a particular effect or phrasing, and this saves the librarian from having to mark over printed bowings. On extreme occasions I have had to port the part over to Photoshop and get rid of them electronically.

Thank you, David Ward and RMK.