From a male perspective, I understand the desire to progress. I don't think I'm that unusual in that respect. If my love and sub let me use a 14 inch dildoe on her today, I'd want to use a 16 inch one tomorrow. I think it's just our nature.

It sounds to me like your wife is the personality type that needs to be led. In other words, she probably fantasizes about being a freak in bed, but has to overcome some moral issues to enjoy it. Talking about fantasies is always a good segway into the actual act(s). Reading some stories from the site is a good idea...but then have her write one with no holds barred. Having her write a story with her as the subject about her wildest sex fantasy would give you an idea of what's in her head. Just don't push her too far too fast. You guys are young and have plenty of time to experiment. I've learned over the years that the best sex is where you BOTH enjoy what is happening. Being selfish (and I've done that), will leave you masturbating alone a lot!

Just a suggestion