Haven't been personally but I have a buddy who takes the family to Sherkston Shores every summer and swears by it... apparently a great beach. So consider that an x2.
As far as Niagara Falls (Canada) attractions, the DW and I were just down to Bird Kingdom and it was great. You can book tickets online for around $10 of your money. Sorry about your luck but we do have the best view of both the American and Horseshoe falls too.
2015 Rockwood Signature UltraLite 8282WS Platinum, GY Marathon LRD, TST 507RV TPMS
2005 GMC 2500HD CCSB D/A, Curt E16, Prodigy P2, Garmin RV760LMT w/BC-20 b/u cam