southern california edison pros/cons of having a separate meter for EV charging

You need to first find out the cost of installing the second meter for option #2.
Then the rate plan between #1 cheapest rate and #2 EV rate.
Here is the formula to use:
option 1 cheapest rate: $x per kWh
option 2 EV meter rate: $y per kWh
You plan to keep your car N years, charge K Kwh per day on average and cost of installing secon meter is P.

Then, you compute N * 365 * K * ($x-$y) . If it is less than P, go with option 1.
This assumes that you can just charge at night under option 1. If not, then you need to compute x by an weighted average of the K KWh that you will charge at different rates on average. If you have solar, then option 1 may be even more beneficial.

I'd think, for most people, the upfront cost of installing a second meter outweighs the benefits it brings.
But everyone's case is different.

 

Get another quote from two other electricians. I see no reason for a subpanel. It's a simple home run using 8/2 Romex with ground. If the charger is exposed to outside weather, you'll need a short emt run from charger to LB conduit body.

If no one is home from 2-8pm, the TOU-B is better.

 

I would add that charging in the early morning means lower ambient temperature. This reduces the battery cooling load.

Bob Wilson