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The bushwhack to Alta comment made me laugh. Pear Lake is above the tree line. Maybe you could tell a little bit more about your physical abilities to help us.
I would say the Pear Lake backpack is comparable to Mt. Sterling or Mt. LeConte in the Smokies. If you can do that, you will be fine on this trip. The off-trail hike up to see the Great Western Divide (you don't necessarily have to go to Alta) from Pear Lake is practically on a trail (that doesn't show up on maps) the whole way. Just head up and east around the north side of the lake until you see ~100 mountains. If you are in shape, it is at most a 4-5 hour RT hike from Pear Lake with no pack. Do some research online and ask the Pear Lake ranger about the route when you get there.
If you aren't capable of doing the tougher backpacks in the Smokies, I would car camp in Lodgepole or in one of the Roads End campgrounds and stick to day hikes.
Actually, I'm pretty sure the ranger isn't there yet. It's still technically winter. The ranger station at Pear is a ski hut in winter, and I wonder if it's even open due to the minimal snow.
The quota period for permits starts May 22 - until then it's self registration at one of the stations outside the visitor centers. And free. But, you can likely go inside the visitor centers and ask questions.
Pear Lake out of season is wonderful and the trip to Winter Alta (not Alta itself) is quite straightforward: viewtopic.php?f=1&t=7169
It might be busy in mid May this year unless you go mid-week. You can see the snow conditions on the Pear Lake ski hut page (which is still open through late April, see http://www.sequoiahistory.org/default.asp?contentID=638): it's mainly a hike to the hut already, though a late season storm (like I had last year in late April: viewtopic.php?f=1&t=10843) can change that for a while. However by mid-May the trail should be clear unless there is bad weather the day you hike.
Maybe you could tell a little bit more about your physical abilities to help us.