If he was actually smart and cunning, he would have married her. Simple as that. No tricks, no swindling, no psychotic tendencies.
He could have been the best man in the world to Silver, treated her with respect and still have his luxuries. But nope, he went the stupid route and decided to screw it all over for himself.
Granted, he didn't have to really love her, but if he had just acted the part (and not half-assedly, like sending her away and being abusive) he would still have everything regardless. Hell, probably even more because Silver would most likely let him run the business in the mansion. But again, no, he went the route that every narcissistic idiot goes on that'll screw them over in the end.
I don't know why but when Charles died I was sad.... I mean, ok he was really cruel but I can understand him a little. When he was a child he had nothing and Geraldine, instead, had everything. Anyway, I really loved this story. It was fantastic.