I think the problem Codemasters have had in the past is that they get carried away with including new content, but only do about 75% of the job. For example, in DIRT 3, they put a huge emphasis on gymkhana. And while it wasn't the most popular move, it was fairly well implemented - but seriously limited by the environments, which did not allow for much variety.
GRID AUTOSPORT should probably stop trying to go so broad. The focus should be on touring car racing, GT racing, and maybe some Le Mans and DaytonaPrototypes. There is plenty of potential there, both for a wide variety of competitions (and therefore cars) - like the BTCC, SuperGT and DTM - and some historical content. Drifting, Formula 3, and what appears to be production cars in race trim might be nice, but it makes me think that Codemasters are again making the mistake of going broad in their variety, but shallow in their content.