Skid.
I accept the sponsor target bug needs addressing but this doesn't alter the fact that one car leagues are not too challenging in terms of resource management, especially if you sign the right sponsors and are fortunate enough not to have to deal with unrealistic targets.
I also realise it's a really tricky problem that the owners/Devs have created for themselves. There are very many high level teams that have stockpiled an enormous number of parts, tokens and game cash over the years, some from farming before it was clamped down on, others just because historically, resource management has been so easy, especially in one car leagues. Even if the one-car format were to be made more difficult tomorrow, these teams would be unaffected such is the size of their stockpiles.
Slo
One car is challenging enough at low levels, it’s the higher levels that offer less challenges, certainly 1 car vs 2 car
I created a new account about 4 weeks ago. I started off by doing Sprint Races then joined a league as soon as I reached L10. I have completed 14 league races in a one-car league and, despite the fact I repair the car and renew engines after every race, I already have a stock of 475 parts. So it is not just for high level accounts where one car resource management is easy.
TBF, I did purchase a special deal a few days ago at a cost of £4.99 but this was simply because I wanted 48 tokens to purchase a T19 driver from my academy and was too impatient to wait.
3 tokens a race in a one car league is more than enough to renew engines every race and still leave plenty to save for other stuff. Not that it's strictly necessary to renew engines in an Elite tier at low level because you're going to finish at the back regardless of whether or not you have a fresh engine.
Up to now I have also had no problem balancing game cash, but this is because I haven't yet been hit with unrealistic sponsor targets.