Matt and group:
The Rauch Planetarium at Univ of Louisville doesn't do a shutdown for maintenance or production, we have only had one major equipment failure which lasted a month but did not cause us any lost shows. Therefore, I can say that for 12 years we have had a traditional plus digital, multi-projector, surround sound theater that has not been down for the public or schools any days.
In fact, we do much more with the dome than most and still have everything working for often 10 to 16 hours per day, 6 and sometimes 7 days per week. Having a full-time tech or Technical Director is the key and I suppose your administrator can say this is a big expense. However, in our case, the Tech Dir is a staffer that runs any kind of shows and the ones that are often the biggest revenue producers like weddings, corporate meetings, concerts, corporate parties and more.
In a more traditional digital dome I think you will find that your equipment may serve you better and more economically than did a bunch or analog, mechanical devices. (i.e. your stars and slide projectors)
My two cents still running a dome with pretty much one of everything that Spitz could put in it in 2000 plus a few more things!
Rauch Planetarium - Univ of Louisville
We are going to the Final Four!