I'm new on this board, so my response may be a bit late for this season. Two good areas that I know about are Mores mountain which is accessed directly from the Bogus Basin OB gates. There is actually quite a bit of terrain around Bogus that is good up until early April. I have some extensive GPS data and Videos on these routes here:
http://hi-adventure.com/gps-tracks-videos/bogus-basin/Also, another area that i am very familiar with, but have just started to venture in is the terrain above Soldier Mountain. There are at least 6-7 good peaks in the 9500 - 10000 foot range that all have great skiing / boarding well into May. Here is the post of my first exploration foray into this area.
http://hi-adventure.com/soldier-mountai ... tion-trek/ BTW, this is an easy drive from Boise and just about 2 hours from my house to the trailhead.
And to see a better view of the peaks, look at the pics in the page on this site:
http://www.summitpost.org/smoky-dome/154193