This is the only sensible route advice, IMHO. I've driven Tahoe to LV several times (winter & summer)... Getting to 50 by the route with the lowest elevation makes sense...
However, my advice to Still Thinking is, after you check the weather forecast east from LV, is to go east on I-40... It is shorter and you will get to I-10 near the FL line...
If there is possible snow along I-40, then you are stuck with I-10...
I should point out that one of the advantages to I-10 is that you can probably earn all your gas and food money by transporting some migrant invaders...
Hadn't though of an opportunity to make money! But, hmm. I drive I-10 yearly to Surprise, AZ for baseball so I'm very familiar with the roads and feel comfortable there. I-40 on the other hand, this time of year can be messy and cold with snow. I'll give up a couple hours for warmth.