I mean the ideal situation in my opinion would be to not have the starter car choice (or any car choice for that matter) be linear at all. Just have it be so, if it's within your credits budget, you can buy it.
GT6 was the worst for this, because you only had 1 car to choose from at the start; the Honda Fit. Only after buying it did the rest of the cars become available to buy.
GT7 gives you a choice of 3 cars instead of 1, so it's a bit better but still not ideal.
There should really be closer to 20-30 cars within the starting credits budget to choose from. Maybe even more. That way if someone wants to start with a crossover/SUV (perhaps they could be a good deal), they can. But if someone would rather start with something else, they can too.
Similar can be said for the events. I'd prefer it if they weren't completely linear, instead being able to enter any event in any order, provided your car meets the rules & you have a high enough License.
Allow the option for someone to enter the Lightweight K Cup or FF Challenge before the Sunday Cup if they so choose. Stuff like that.