Avanti Mansion has all of that!
I had my cerememony & cocktail hour at the Butler Mansion - http://www.visitbuffaloniagara.com/buffalo-architecture/buildings-monuments/butler-mansion/
the rose garden at delaware park is beautiful - they have an indoor reception area that is right on hoyt lake. http://www.visitbuffaloniagara.com/listings/index.cfm?action=display&listingID=5151&menuID=473&hit=1 Here is the caterers info: http://www.magnoliabuffalo.com/wedding.php
I loved the Timberlodge. It has all that you are looking for, and Anna ( the coordinator) is awesome. Good luck!
Depending on what feel you want there are some great options. The Avanti Mansion is beautiful and elegant. Pearl Street at the Lafayette has an outdoor area for ceremonies, it has a more rustic feel yet still beautiful. Kloc's is another fantastic location; beautiful gardens and awesome indoor/outdoor areas for receptions. Hope that helps. Good luck.
Check out Kotecki's. We had our wedding and reception there and it has everything you've mentioned for a very reasonable price and very beautiful venue.
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