Angron. He has the power of a Daemon Primarch and all the benefits that comes with it. We shouldn't use examples like "he isn't used to having wings" and "his anger could be used against him" in my opinion. He is a Daemon Primarch, so mortal experience like getting used to flying may not be the same as humans.
The same goes for the argument of "being too bulky". Space Marines are very bulky, but despite this they are inhumanly fast compared to normal humans and also quite agile despite their bulk.
Also, who knows what battles Angron has fought? In his time as a Daemon Primarch, he may have fought thousands of batlles in the warp against rival daemons and Princes.
However, despite all this Sanguinius is still...well, Sanguinius, so who knows what could happen? I'd rather have a killer than a fighter on my team, though.
Are you actually expecting an Inquisitor to teleport in to your house with a squad of GKs and stomp all over the little plastic space men you just played a homemade campaign with?