There aren't enough guys in that division for him to consistently fight 3+ times a year like guys can do at 170, 155, and 145. I took a look at the HW rankings and it appears that all of the top 15 except for Stefan Struve, Travis Browne, and Alexey Oliynyk are booked. Browne is not an option until his investigation ends in his favor, so strike him out too. The sad thing there aren't that many good fights to pick from outside of the top 15 since the talent pool is so small.
The above problem is one of my gripes with heavyweight, and why I just don't get excited for any fights in the division. The other reasons are that the quality of the fights in general aren't as good as the lower more stacked weight classes, due to the big boys having comparatively lesser technical skills and bad cardio, save for a couple of guys. The biggest problem for me though is that the few guys who are entertaining to watch only fight twice a year at most such as JDS, Velasquez, and Hunt, so it makes maintaining excitement in the division tough. Partially this is due to guys getting injured, but also because the division is so thin, making it impossible for them to imitate lighter weight fighters such as Cerrone, and McGreggor, who both have fought four times in the last 12 months, and are about to fight again in December.