Upload & Sell: Off
I've seen people with far less talent post about doing their first wedding here and they got less criticism for it Probably because those people were doing it for free and you're charging, but still....
I think you'll do a very decent job. Your website/portfolio has a lot of great shots, and I'd say your overall ability level is way above most people that post about doing their first wedding or any hack off craigslist. You really should have insurance, but I completely understand why you don't right now. Doesn't make it correct, but I understand.
One little tip I can give you for the formal/group shots....I know you said space will probably be limited, but use the longest focal length lens you have, whether that be the upper range of the 70-200 or a 135L or whatever. The telephoto compression does a lot to make formal/group photos look way better than anything you get with less than 85mm.
Everyone is giving sensible advice and each point is very valid.....but sometimes you just have to get out and do something in order to grow and flourish.