I think I'd follow the above advice to raise the drain and use concrete or 'leveler' to bring the floor to the desired height/slope and then tile that room with ceramic tile. A good tile guy can cut in tile on angled surfaces to make it look great. And that eliminates the aesthetics aspect of the patch. Yes, it will cost more, but with that solution you will avoid the problem of walking in there daily and wincing at the visible f-up for the rest of your time there. Sometimes taking the pain up front is well worth the price compared to a daily reminder of something you hate. It's one of the reasons I only buy decent cars because I spent plenty of time with old stuff that I hated walking up to in the parking lot every day. Life's too short to be unhappy.
Rob