I don't really care a whole lot what others think, if someone doesn't like how I've got a bike set up then they are free to offer to buy it and if successful then they can set the bike up as they see fit.

As to the OP's bike I have to ask what the intended use of the bike is. If it will be sold then I'd say keep or repair the disk or find a replacement for the bike. If the bike is a keep but will be left parked in public places and left unattended in public or company bike racks where the derailleur might get bumped and the OP might then unaware of the new misalignment of the hanger might shift into the big cog and suddenly find the chain playing games with the spokes thereby causing him panic as he realizes something is amiss, in this case as well keep the disk IMHO.

But if the OP just wants to run the rear hub and spokes unprotected and is willing to take the risk by ensuring his mechanical skills are sufficient and if the components are as well sufficient to remain in tune then I'd offer to suggest that the OP is free to do as he chooses.

As to pie, had a slice yesterday, Macadamia Cream, kind of rich but tastey.

Singlespeed conversion? Go ahead and dump the disk.