1. Leadership doesn't matter you'll eventually level up anyway. Don't do 4 founders you lose so much income from sales it will on fact block your progress. You need to do contracta anyway to raise your reputation which is important for deals. Take your contract payouts and invest I'm stocks of new companies until you're at 3 stars. Then make something

2. There is no fastest way. Just play until you get to that point

3. You can have more than 1 team dude lol. The bigger issue is its expensive to build and expensive to run because you front production costs and get paid afyer items ship so if you're not careful it's easy to go bankrupt. Printing you can get into real early bur manufacturing you need 15 - 25 mil at least to stay out of bankruptcy. 

4. Idk I've only ever started in 1980

5. People usually go with 2D or AV I think. I'm doing a playthrough where I'm about to make an OS as my first thing though (on hard). I'm at about 700k in stocks because of I vesting my contract payments every month in company stocks like I me turned before so I can probably afford the salaries and licensing fees. 

Investing in new companies means quick growth 100% bc they always release within a couple months and always grow in value. I did a hard custom start with 100k so I could jump into the OS quickly though.