IMO the entire leveling system has a fundamental flaw, in that there is very little mechanism for chance. As I understand it, some of this will be addressed with the new design system, but right now the critical issue is that progression in this game follows a very rigid path. You level up, you buy the facilities, you get the KERS, you build out your car via a small set of components, you sign the same top-level partners, and get drivers with great health and talent numbers.
With that formula, it becomes simply a matter of time before you end up at your destination - and then iGP becomes a simple question of whether you want to keep dedicating the time to do it.
Realistic uncertainty is hard to pull off in game design but it offers the most enriching end-user experience. In real life racing, the "magic mix" of elements that have to come together for a team to be successful is a potpurri of disparate factors. Translating to game metaphors, you could get your level 20 driver and max your component levels with the Murk, Seashells, and Bridgerock partnerships, but you might still end up not dominating or even backmarking. The intangibles of luck, team chemistry, and the ability of team personnel countering innate talent with hard work to achieve breakthroughs that should not be possible on paper all contribute to that unpredictability, which is why many of us became race fans in the first place.
I suspect that iGP's future prospects will be heavily contingent upon whether they can introduce that element of entropy to the game. I feel optimistic considering how good the game is in these early stages. Simply adding layers of complexity to the model is not necessarily the way to do it, though. When I was working in game design years ago, our cafeteria had a stand-up Asteroids arcade game. We played it often to remind ourselves that, in the end, all the bells and whistles in a game count for exactly nothing if the basic gameplay is not addictive.