3 things I'd be changing (amongst many others):
1. More teams. The Concorde Agreement stifles competition and besides Ferrari, McLaren, Williams (and I suppose Red Bull) it seems like near every other team on the grid keeps getting bought out every season or 2, and it makes it harder for a casual fan to follow along. Plus, more teams means more cars, more opportunities for genuinely talented drivers and the next Colin Chapman/ Adrian Newey to shake things up. Sure, there'll be the odd USF1/ Andrea Moda/ Life but it's a small price to pay for a more competitive grid.
2. Cap total races to 18 a season. Makes every result count that little bit more, plus curbs these Herman Tilke clones being put up in countries with a tonne of cash to throw but little national enthusiasm for the sport. Monaco could stay, but it needs to be investigated if sections of the track could be expanded/ opened up (thinking the harbour front chicane) to allow more passing opportunities. Monaco, Silverstone, Monza and Spa should all automatically be on the calendar, plus races in Germany, Japan, Australia and other countries that have always had a healthy motorsport following.
3. Bring back the grid girls. Trying to appeal to sour-faced cat ladies is pointless. What's more empowering than allowing these girls to get paid to attend a prestigious event AND ad to their portfolio? If there's ever another female driver on the grid, get a couple of footy players/ male fitness models to be her "grid boys". Gender equality and everybody wins. Like I said, the sour-faced cask wine drinking cat ladies aren't going to watch F1 anyway.
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