The San Jacinto area would be an excellent choice for a 2-3 day backpack loop. Use the PCT as necessary but not exclusively for the best experience.
I remember this area well as a zone of giant virgin forest and our first encounter with 100% snow on the trail. In 2005 the entire area was covered in snow probably well into June but 2012 and 2013 had basically no snow at all; a February hike would have been pleasant.
I followed the mountain fire closely and it appeared the divide took a nasty hit; unfortunately it now likely has a character like Combs Peak environs. However, as it moved north and turned the corner around Red Tahquitz up towards Saddle Junction the winds calmed and hopefully it just crept along down low. In my mind this flatter area is the most special of the zone and hopefully this fire did its (much needed) job of clearing out some of the woody debris without killing the monarchs. As per natural design.
Let us all hope; I am eager to return and observe.
One more thought on the backpacking: you should also consider San Gorgonio Wilderness. Not the PCT portion, but around the mountain itself. Magnificent forests there as well.
Hans Berg