This is bunk... CraigsList is no more dangerous than hooking up on Tindr, Grindr, Squirt.com, or even LPSG, or any other "meeting/dating' source. CL is just much larger and worldwide, so it gets the bad press when people do something stupid, like not first meeting in a public place, and end up in trouble, which, statistically speaking is a rare occurrence. If you are victimized, your CL messages lead right to the perp's profile and then to their IP address. Your "garage sale" ad is no more or less safe from attracting burglars if placed on CL or in your local newspaper.
CL just got a bad name because one killer made for a lucrative, tabloid style TV movie. But, HOW you hook up is not the topic of this thread.
You don't say whether you are a male/female couple or male/male, but either way you aren't going to find a "hook-up" that appeals to both of you more than a couple of times a week, and what a big effort that takes! So, I doubt you are going to have a lot more sex without going behind your partner's back. I'd recommend enjoyable, uncomplicated, masturbation, and A LOT more discussion with your partner, before having a wedding.
A/B