Know any big, fragrant, medium-light orchids?
 

So as of yet I don't think I have enough light to get a Cattleya to bloom. I have a large east facing window that gets about 3 hours of sun a day in addition to T8 lights that are on 12-14hrs a day...maybe more...I don't keep careful track.

I do like that Cattleyas have large, bold, fragrant blossoms, but since I don't think I'd have enough light, I'm wondering if there is a lower-light replacement variety you'd suggest.

Stanhopeas, Gongoras, Acinetas and other members of the Stanhopea alliance and hybrids thereof will fill the bill.

Burr. Nelly Isler is a treasure. Oncidium Sharry baby smells like chocolate and vanilla. Oncidium twinkle is also nice and is compact.

My Dend-phals seem oblivious to light levels, give nice big blooms (multiple) and come in various light colors. They are reasonably easy care.

I say go for it!!!

Get a big Catt.

I have three Pot. Cheryl Winkelman "Chris" (among others) from Hausermann's in an east facing window. They have bloomed for years with no supplemental light. In fact they are budding up right now.

Nice and big and fragrant.

I have LC purple cascade which has a wonderful fragrance and blooms during the fall and winter. An East window would work fine, especially if you can put it outdoors during summer.
Actually, if you have added lighting it should be perfect for most Catts.