Hi everyone!
First, I enjoyed reading many road-related info on this forum. Decided to be a member so I can ask this questions (as well as future participation)

Short story... I was supposed to Fly to Florida for a wedding to attend but ended up going with 12 foot Penske truck (front end looks like a van) for my mother-in-law she's moving from Riverside, CA to near Tampa, FL for her health reason so I volunteered to go alone bringing her minimal household stuff.
I sometimes like to take rural roads if something I like to do, I already experienced driving "America's Lonest Highway -U.S. 50) between Ely and Fallon in Nevada. Sometimes I have to take interstates as well.
This will be during early November.
1- Sunday 11/3, pick up Penske 12' truck from Sacramento, CA and drive empty to Riverside, CA to load it up there. I'm thinking of taking I-5 to LA area, I-210 East to CA-57 then CA-71 and finally CA-91 to reach that destination. Is this a good drive especially it would be on Sunday? (Trying to avoid traffic in Southern CA

).
2- Monday 11/4, Honestly I have no idea which is better driving from Riverside, CA to Albuquerque, NM!
The options would be I-215 north to I-15 to Barstow then I-40 all the way to ABQ. The second option is I-10 to Phoenix, AZ-202m AZ-87 to Payson, AZ-260 to Heber, AZ-277 and 377 to Holbrook, AZ then take I-40 to ABQ.
or I-10 from Riverside to Exit 117 for CA-62 north to Twentynine Palms and take local road North Amboy Road to Historic U.S. 66 to get on I-40 near Needles, CA.
3- Thursday 11/7, Which routing is best from Albuquerque, NM to Austin, TX (specifically west Austin along U.S. 290 near Lake Travis)?
4- Sunday 11/10, Planning to drive 71/290 from Austin to meet up I-10 all the way probably to Mobile, AL where I'll stay overnight at hotel
5- Monday 11/11. Planning to drive I-10 from Mobile to I-75 in Lake City then head south on I-75
6- Along these routes I mentioned above, what attractions to stop for and must eat unique food?
Oh I plan to stay with family/friends for couple days both in Albuquerque and Austin in case you were wondering why few days apart

Anyone have experience with 12 foot Penske truck as to gas mileage? how many miles per tank on average?
I know I asked alot, hope to decide which routing I would take after hearing ideas and suggestions from you all.
Thanks in Advance!
Salvatore