Charlie is a disabled old man with a cane and a bad smoking habit, until you play him off taboo.
Off taboo, he's a machete wielding lunatic who swarms his victims with a pro football player, dogs, a literal assassin and his trusty secretary. He uses Dig Deep and Drawing Thin to ace will/evasion checks, physical conditioning or combat training to buff his machete and loves explosives. He's even ever vigilant for eldritch horrors, and has no problem going Toe to Toe.
Don't count this guy out, unless you play taboo. I'm not sure how to play him without the ridiculous resource generation from Drawing Thin.
Off taboo, starter deck should be In The Thick of it, Drawing Thin x2, Ever Vigilant x2, Jessica Hyde, Peter Sylvester, Physical Conditioning x2, Machete x2, Guard Dogs x2, Dynamitex2, Hallowed Mirror, Dig Deep then whatever you want.
This mitigates his biggest problem which is playing assets, and let's you do one (1) really good combat check per round. He's otherwise extremely tanky, but due to the fact he only gets one "good hit" hes dependent upon card effects that guarantee damage.
That's not enough to be a solo mob healer imo, and he will usually need to be paired with someone who can handle enemies just fine on their own (i.e. trish) but his strength comes from being able to do anything really, really well, one time per round.