I'd like to plan a backpacking trip for this summer that involves a Mt. Whitney summit. I'm just in the beginning stages, but already have some questions. Here are the three possible trips I am thinking about, in no particular order.

A. The High Sierra Trail to Whitney Portal
B. Onion Valley to Whitney Portal
C. Horseshoe Meadow to Whitney Portal

Here are some things I am thinking about. I know most of these are wide open questions, but I would appreciate any information or opinions you can provide:

Q1. If you could take any of these trips, which would you choose and why?
Q2. What time of year should I get the permits for? Snow/ice, mosquitos and bad weather are concerns.
Q3. How many days do you recommend for each trip? I understand that this is a tough question to answer, but that's why I am seeking help. I believe we can hike 10 miles per day comfortably, but since I am in the early stages of planning this hike, I am unaware of any particular parts of the trail that may slow me down or be more difficult than they look on paper.

Permits
Q4. What permits are required?
Q5. Which trip has the easiest permits to obtain? The hardest?
Q6. Since I would be exiting at the Portal, does that mean I bypass the need to enter the lottery?

Transportation
Q7. This is what I've found searching Google. Any problems with these ideas or do you suggest other options?
A. High Sierra Trail - Take Greyhound bus from San Bernardino to Visalia (~$50). Take the Sequoia Shuttle(~$15) from Visalia to the trailhead. Have someone pick me up in Lone Pine.
B. Onion Valley - Drive my own vehicle to the trailhead. Take East Side Sierra Shuttle from WP to OV ($110 first passenger, $25 each additional.)
C. Horshoe Meadows - Drive my own vehicle to the trailhead. Take East Side Sierra Shuttle from WP to HM ($120 first passenger, $35 each additional.)

Q8. If leaving a vehicle at the trailheads, are parking permits or special arrangement required?