Task queue is the way to go. I hate PW (Please Wait). I can't use Pronto for new jobs, but I had a task queue that I would pass from Activity to Activity. After you've developed the capability it will fundamentally change your whole approach. Rather than 'Projector Power', PW, 'Projector Input', 'Receiver Power', PW, 'Receiver Input', "Blu-Ray Power", PW, .... The sequence will become 'Projector Power', 'Projector Input (+60.00)', 'Blue-ray Power, 'Receiver Power', 'Receiver Input (+1.00)', 'Start light show', 'End light show (+60.00)' ...

While it's hard to bury a 60 second wait, for more reasonable devices I could start the slowest device (usually the TV), follow through with setting up the other devices and dump the user at picking the cable channel. By the time that the user is done with picking the cable channel, most of the other devices are ready to go and there is no need for a PW. The whole system seems more responsive to the user.

I also keep track of a unit's power status (when practical) because there is no point in waiting 60 seconds for a projector if it is already warmed up.

This is also handy for cable boxes that respond slowly. I use icon based cable channel selection and the digits must be metered out at a pace that the box can execute. I'm also very fast when I manually enter channel numbers. Since the box cannot execute at that pace, there will be missing digits and frustration. I queue the digits as entered and meter them out to the box at a more reasonable pace. Keep the inter-digit wait time symbolic. This will allow you to optimize the digit spacing by editing a single constant. (cable boxes can change or be updated)

I used an RFX9400 or RFX9600 for IR commands in order to avoid issues created by concealed devices or the user pointing the Pronto in the wrong direction. (It's unreasonable to expect the user to keep the Pronto pointed in the right direction for the full 60 seconds)