Matt Hughes hasn't been a title contender for a long time. Most see him as a legend on the down side of his career, able to add some star power to a otherwise lacking card. He has never backed down from facing top competition and has always been willing to do the UFC a solid. So what is left for Hughes if he decides not to retire?
If Hughes ever fought again, you would need a match up that makes sense in terms of a name and one that would give Hughes a chance to win and potentially retire on a good note.
I think that Jake Shields works. Both are coming off of two loses and Matt Hughes probably isn't going to get knocked out by Shields. Hughes striking did look improved against Koscheck (until he got knocked out of course). Both are great grapplers and it would be an interesting style match up. If Shields wins, he gets an impressive name on his record and becomes relevant again. If Hughes wins he gets a great victory to retire on and you can cut Shields. Shields has performed pretty poorly in his three fights in the UFC. He gassed against Kampmann, made more of an attempt to survive the GSP fight than to win it, and got knocked out by Ellenberger. A lost against Hughes would surely warrant getting cut.
Although Dennis Hallman is dropping down, if he loses his next fight or is pulled out, I think this fight is a good one. I would like to imagine that Hughes would love a chance to avenge a dirty pair of losses against Hallman's infamous dirty pair. Hallman gets another payday and I'm sure everyone's happy. Except Hughes if he loses again.
The last fight is random and probably will never happen. I wouldn't mind Hayato Sakurai fighting Hughes in a rematch. Of course Sakurai has no business in the UFC, and the first bout was no classic by any means. Sakurai shares something with Hughes. They were both at one point the top guy in their weight class, and wouldn't be an offensive novelty fight.