Spicy Miso Ramen was a much better choice than Tonkatsu Ramen for first timers.
Shoyu is ok.
The management here is great and service is on-point. I would imagine the Tonkatsu and Shoyu Ramen could do with more oil and garnishing (green onion and bean sprouts, perhaps), as some Japanese styles cater.
Mitsuwa in Arlington Heights uses this method for their ramen (sesame included and more oil use). They are probably one of the most established ramen places in the Chicago suburbs, perhaps even the Chicagoland area.
Daikokuya, the most reviewed on Yelp! and one of the most popular ramen destinations in LA, uses a light taste similar to what Ozu offers here. Their noodles have a firmer texture than what Ozu uses, but again, taste is subjective and even my taste will not necessarily be what others or the majority wants.
In all the ramen places I've been to, taste is subjective, but I will say again that the Spicy Miso here is better if you like a heavier kick to the taste. Shoyu is light, if not a bit underwhelming, and I found the Tonkatsu to be rather bland and too salty.