Let's break down his career up to Sonic 4 and Colors:
Sonic the Hedgehog 3 & Knuckles (1994) — Senior Game Designer
Brilliant
NiGHTS into Dreams (1996) — Lead Game Designer
Brilliant
Christmas NiGHTS (1996) — Game Designer
Ditto
Sonic 3D Blast (1996) — Game Concept Design, Special of steam turbine and gas turbine systems Design, Saturn Enhancements
Fun, not amazing. Saturn version was much better
Sonic Jam (1997) — Director
The best Sonic compilation ever
Sonic R (1997) — Game Design Director
"Meh" now, good from a nostalgic standpoint
Sonic Adventure (1999) — Director, Character Game Designer, Chaos Game Designer, Level Designer
Excellent
Sonic Adventure 2 (Battle) (2001) — Director, Game Designer, Enemy Game Designer, Level Designer
Excellent
Sonic Adventure DX: Director's Cut (2003) — Mission Mode Game Designer
Meh
Sonic Heroes (2004) — Director, Level Designer, CG Movie Director
Decent but overall a failure, would have been better without gimmicks
Shadow the Hedgehog (2005) — Director, Lead Game Designer, Level Designer, Scenario Writer, Movie Supervisor
Failure, would have been alright without gimmicks
Sonic the Hedgehog (2006) — Special Thanks
Awful game, but look, he didn't make it!
Sonic Rivals (2006) — Director, Concept Design, Scenario Writer, Producer
Never played it, some like it and others hate it
Sonic Rivals 2 (2007) — Director, Concept Design, Scenario Writer, Producer
Again, never played it. Some like it and others hate it
Nights: Journey of Dreams (2007) — Director, Producer, Lead Game Designer
Not good due to control issues and pointless side-quests. Were this to be developed for a normal controller and streamlined to be an arcade-like game, it would have been great. Boss battles were fun
Sonic Unleashed (Xbox 360 & PS3 Version) (2008) — Level Design Special Thanks
Not sure what this means, perhaps he gave level design ideas? The daytime stages were enjoyable level design wise
Basically we've got greatness when he is a game designer, hits and misses when he's a director and more often than not those misses are due to gimmicks. I'm going to say something and you can do what you must (expel me from SEGAbits forever, remove me from your friends lists, force me into a room with Bentley Jones), but based on his past I'd still give Iizuka a chance.
It seems when he doesn't have odd control schemes and gameplay gimmicks he can do more good than bad. He has a great early past with 2D and 2.5D game design, and thankfully both upcoming Sonic projects are heavy on those aspects. Gimmick-wise , 4 has the homing attack and Colors has simple power-ups which are pretty light compared to werehog, guns, hero/villian mechanics. We shall see, we shall see...
If it were up to me, I'd give somebody else the job. But since I cannot control who SEGA puts on their projects, I'm leaning toward the positive on his next projects.
