I don't see the homologation thing as something bad. Yeah, I know the good thing about Forza was racing a crap can, against a full on racer, but I'm more keen on having a proper field of LMPs, GTs, etc, than a franken-field. The class system in Horizon 3 works better because it's more like "do what you want" game. Take an F50 through the field? Sure! Drop a trophy truck off a cliff? Go ahead! Even more, I don't see the whole point of a GT3 racer in a game based on open roads, I think that was a bit of a miss, but not too bad IMO.
The car collecting "game" within the game I think it's alright. Specially because there are cars I would never buy and drive. And by doing so at least you get to discover some hidden gems on the car roster. So I think it's okay.
And yeah the menus are a bit messed up, but no pCARS1 level of mess up, I guess.
The matchmaking... Oh it's so dumb, it always connects me to races that are already happening. Specially on the new GT Endurance races (IMO the best races), the matchmaking just connects you to a race that is 1 of 20 laps... I just disconnect and reconnect in another lobby just to see that it has the race started... Ughh so annoying.