I actually like the racing in Arcade mode.
First off, Arcade mode is very important for the sake of OLR.
Hotlaps and Multi-lap races benefit from several elements in the Arcade Mode.
All of the cars in the game are availible, which is a big "plus" compared to the arc mode from GT3 (although the exclusion of GT mode garage cars is enough to negate that "plus").
The adjustability of the arcade mode is one thing I really like about it.
Tire wear, number of laps, difficulty, all of that stuff is new to arcade mode.
Likewise, the detail in each of those is suprising as well... Time limits are new and multi-lap races benefit greatly from the system.
Contrary to the popular opinions, I don't find the cars in Arcade mode to be very bad.
Simply put, you just can't adjust them.
Otherwise, I find that the Arc cars handle almost exactly the same as their GT mode counterparts (stock).
My only beef with the Arc mode (besides no personal garage cars) is that you can not put racing tires on street cars (same goes for street tires on race cars).
Overall though, I feel like Arcade mode contributes to the game on several levels. 👍
Any one of you may disagree, but just so you know, I'm not alone.
http://db.gtrp.de/gt4_arcade_cars.php
And that's only for Time Trials!
Add in "single race" and you've got yourself plenty of fun if you can just get past the un-adjustable car suspensions (as well as the stigmas attached by the haters).