Well, Wing Commander's MANIAC just was a wanker ( I liked him, though, especially coz he reminded me of the good old BACK TO THE FUTURE films, don't know why ???
)
EACW's Geezer behaves like maniac, but it is more of a stress reaction.
At beginning of EACW he sees two of his friends die right in front of his eyes, and he playes the maniac coz he wants to distract himself from his own memories.
SHADOW, the leader of the Alexander's alpha squad, doesn't appreciate GEEZER's attidude, but with the time being he comes to understand his motives, and... finding new friends, Geezer starts to get normal again. Slowly, of course. Geezer NEVER gets normal again.....
In a way, Geezer's character has some depth, although he seems to play the lunatic.