I see the threats to Bones looking something like this.
1. Machida- Hard style to crack, Bones gets sloppy a lot and Machida has the best counters in MMA. Sumo can help him in the clinch where Bones gets most of his takedowns.
2. Shogun (Healthy)- Hits hard as shit, reckless style leaves guys open, good off his back.
3. Hendo- Top 4 in the clinch with Bones, Page and Randy. Hits hard as shit, unbreakable chin.
4. Rashad- Knows Bones better than anybody, fast when he's not tired, great wrestling.
5. King Mo- Best wrestling pedigree at 205, hits hard, decent boxing.
6. Phil Davis/Alexander Gustafsson- Put them here since they train together, are the two biggest prospects at 205 and both have another couple years before they're ready for Bones' level. Davis is a great wrestler with weak standup and Alex is a great striker with good wrestling. I'm not sure if Davis will ever put it all together since he panics when he gets hit but I think Alex can if they don't rush him like they did when they had the two of them fight in their respective 2nd fights in the UFC.
Feijao might have a good shot in a couple years, would like to see how he does against the top 10 UFC guys. If Mousasi would stop being a dick and come train in the US he could work on his wrestling which is really his only weakness. Mousasi with takedown defense could trash Bones on the right night.
That all being said I still think Bones beats all of these guys more than 50% of the time. Unless someone lamps him and he gets Brock syndrome and is terrified to get hit.