I've written before about the alternate service my congregation has on Rosh Hashana and Yom Kippur, the Ruach service. It's very much in the style of our Shabbat minyan -- musical, participatory, full of spirit, and way more traditional than the Reform norm. Originally my rabbi led this service, though a few times he had to leave early (to be at the main service) and said "Monica, take over" -- once with a new prayer book I had not seen before, with the high-holy-day-only special liturgy. (I love the trust he places in me but that one was "exciting".) Then last year he couldn't be there at all and asked me to lead it along with somebody else. The other person was, to put it mildly, quite problematic.
This summer we hired a new associate rabbi and she's been coming to the Shabbat minyan and enjoying it. My rabbi asked the two of us to lead this service. I'm very pleased that he kept me as part of this; it would not have been completely unreasonable (in our congregation) to say that when we have an actual rabbi, the lay person is no longer needed.
We'd only led one service together (a minyan service when the senior rabbi was out of town), but it turns out that she and I work really well together. It usually takes people collaborating on services a little more time to start developing the "hive mind" where things just go. (Yes, of course there's a lot of prep involved, and sticky notes in the book for who's doing what in places, but even with that, services led by people who aren't used to working together often don't look smooth.)
Rosh Hashana was last week and the service went very well. It flowed, it wasn't rushed, and we finished exactly on time. We got lots of compliments. Yom Kippur is Wednesday and I expect we'll have even more people then. I feel really good about this.
Also, chanting Unataneh Tokef on Rosh Hashana clicked for me. I don't mean musically (though that too); I mean the text. This is a grave prayer and I felt it in a way that I haven't felt it when merely reading or listen to it. Oh Rosh Hashana it is written and on Yom Kippur it is sealed: who shall live and who shall die, who shall be content and who troubled, and so on. Since Rosh Hashana I have attempted to do teshuvah for some specific things, and I hope that come Yom Kippur, when I chant this same text again, I will feel I succeeded.