Fwiw, it might be worth mentioning that in case you use lots of sample based instruments, CPU useage will actually go up a bit (well, it's RAM useage, but in the end the result is less computing power), even if you don't use the instrument, let alone the project will take longer to load. So it's probably not a too great idea to have your templates stuffed with tons of orchestral instrument instances if you only need them occasionally.
Others than that, with Logic you can have a truckload of the most CPU hungry instruments and effects in your templates, all ready to play but not using up any of your precious CPU resources in case you don't actually play back something through them. One of *the* great things with Logic and something almost no other sequencer offers.
- Sascha