Our plan is to arrive at Government Camp in time to explore Trillium in the late afternoon (maybe some sunset light) and then return before sunrise the next morning.
Arrival to Lost Lake would be on up in the day and lighting might be flat by then, plus the water would probably be choppier than in early morning. So, your input is much appreciated. Notoldyet had camped at Lost Lake and had the chance to see it under optimal conditions, I would think. As we all know, in photography it's all about the timing.

With the option of the two additional lakes (Timothy or Lost) we will probably play it by ear based on the weather and our fatigue. This will be the last day out and we were hoping to get back to Portland in the mid-afternoon in order to prepare for the flights home. At one point in the planning I was considering going over to McKenzie Pass and up to Santiam Pass in order to swing by Scott Lake and Clear Lake--those are both beautiful lakes to photograph IMO! Just didn't have enough time to do it all.