Yup. I moved from L38 to 39 just by grinding the F1 Seasonal Races.
Any idea roughly how many times you grinded?
I don't think GT5's F1 cars "suck", though I have to say I'm a bit of a Ferrari fan. The licensing problem may get worse. Top Gear? ALMS? Okay, so GT got WRC, NASCAR and Red Bull for a little while, but what will be the next licensing problem...?
I've been reliably informed that EA and Microsoft have been sub-licensing Porsche and Ferrari to each other for N4S and FM. A good deal for both parties as it's saving both some money and still delivering for gamers. Not sure if that deal is still in place now though or whether EA are preventing Microsoft from using Porsche in FM4 (I don't think there's any N4S games on the horizon so perhaps they're saying no for now).
Microsoft owning the Ferrari license and preventing it from being used by Sony (see Outrun Online Arcade and how that was pulled from PSN as an example) is a problem. Then there's the FIA... Then there's EA and Porsche. Sigh!
On that note, it's probably a good idea for Polyphony Digital to exploit other avenues and make as much DLC for GT5 as possible. Improving, optimizing & extending GT5 on PS3 until the end of this generation is an incentive for people to keep buying the game (or re-buying it if it was traded / sold). Bolstering the 1000+ cars with directly licensed DLC cars from other manufacturers may be one way of boosting interest (obviously the DLC will have to pay for the license). Exploiting the marketability of old GT4 / GT-PSP tracks is another.
Existing GT5 cars (like these Ferrari F1s) aren't a problem that will ever be fixed because the game is already pressed and on-sale. Shame, but at least they can still be enjoyed - even in their limited ways. It would be good if these F1 cars were on sale for say CR 5,000,000 instead. Perhaps then they would be considered more worth the time people spent saving up for them.