Hi Liz and fellow organizers :)

Here in Ottawa, we have two situations that happen which might be similar to what you are describing.

To set the scene:
-We have a monthly Wednesday night 'local talent' contra dance were any of our local callers are welcome to call. (Cheaper event to attend; no talent gets paid)
-We have contra dances two Saturdays a month which are a mix of local and away callers (Cost to attend; much bigger dance; talent gets paid)
-We have 5-6 double events a year where there is a special afternoon dance in addition to evening contra dance. (Poster attached for that)

Only on very rare occasion have we hired local callers for our double dances.  This is because we use those events to bring in expertise from elsewhere AND the fact that the talent gets paid for two events rather than one makes it possible for us to bring in talent from away, which we like to have on occasion.  The only time we've had local callers for these events is when we did a beginner waltz lesson, beginner hambo, and also a split event with the Ottawa ECD and contra communities.  In those cases, we chose people who had expertise in these areas.

Approximately half of our local callers call at our Saturday dances.  Mostly this is when we feel that they have enough experience and we'll start them with a half evening.  We haven't had any issues with people who aren't ready wanting to call on a Saturday night. However, we have had the experience of having local callers with a bit of Saturday experience not necessarily being ready for more.  What we've done to deal with these issues is that we've made an open policy of 'we want feedback on our organizing and we want to be able to share calling feedback with you'.  Then the main program chair will check with our committee for feedback after the local callers call on a Saturday and share feedback from the committee.

Not sure if this helps...
Thanks,
Emily in Ottawa