I've got you covered on the Niagara side of the house as well. I've been coming on these boards looking for advice for a long time, and now I can finally pay it forward!
A lot of people like to dump on the Falls because of the "Tacky" touristy side... especially Clifton Hill. But really, they don't get it. Niagara Falls has ALWAYS been "Tacky-Touristy" ever since they were discovered way back when. There is so much history of the Falls and it's always been a place for grifters and sideshow artists. Love it for what it is, because it is no question an authentic experience... not contrived or phony, its the Falls.
All that said, there is so much more to Niagara than Clifton Hill. As well, I see the Falls usually at least once a week, and I never tire of seeing them... never. They're just awesome (at least I think so). Gunnerbob has a lot of the usual stuff covered pretty good. There is so much off the beaten path stuff as well.
If you've got time, drive the Niagara Parkway to Niagara-on-the-Lake. Churchill called it, "the prettiest Sunday afternoon drive in the world.", and no doubt I agree. The Niagara Parks Commission works hard to keep it that way (your $20 parking fees at work!)
Once in NOTL do the Jet Boat. Its my favourite way of experiencing the Niagara, even though the price tag is steep (but worth it). The best seat is four rows back on the right... trust me! Niagara-on-the-Lake usually wins the title of Canada's prettiest town. They work hard at it. I find it funny how people rip the Falls, and praise NOTL. However, the former is the truer experience, and NOTL is the contrived one, as it was for years a blue-collar ship-building and farm town... In any case, you have to go, if only to grab and ice cream on the strip, and to check out all the luxury homes. I'm not really one for mansions and all, but the residents of NOTL are really respectful of classic architecture... definitely not your suburban McMansions. Of course there's the whole winery thing too, but that's best without kids. If like dessert type wines, grab a bottle of ice wine somewhere (anywhere). Otherwise, the whites here are world class... the reds are hit and miss mainly based on vintage.
If the price tag on the Jet Boat is too steep, another lesser known way to experience the mighty Niagara up close is to hike the Niagara Glen trails across from the Whirlpool Golf Course... best of all it's free. My friend hikes there everyday.
If your grabbing dinner, we like Napoli restaurant on the corner of Stanley and Ferry in the Falls. Its mostly locals in there, and they really treat you well. The complementary focaccia is the best I've had anywhere, as is their oil to dip it in. They've always brought us 2nd and 3rds which we graciously accept! My wife loves the tiramisu. I usually order the "pizza of the day". Last time I had a roasted pear / brie / prosciutto / caramelized onion white pizza. Awesome!
Anyhow, if there's anything else, I'm happy to help. I owe it to these boards. Like I said, there's so much here in the Niagara area. If it had mountains, I probably would never leave!