If you look at all around players Horford has to be around the 3rd best big man in the league. I don't know how I'd rate them but I've seen him ranked much lower to higher.
1. Cousins
2. Davis
3. Horford
Love
Kristaps
jordan
Marc Gasol
Drummond
Whiteside
Myles Turner
Towns
Gobert
etc...
Some teams have gone so shooting happy you have to put durant in there even. after that you have specialists like Bogut, Noel, Okafor. Al j isn't what he was used to be.
If anything Towns is a bit overrated because of his age.
Some of these guys are pure PF's too. Blake Griffin, Millsap, Ibaka, Aldridge, Favors etc.. Even Love and Davis are more power forwards. Horford can do both.
People will rate Towns better than Horford but that's not the reality of it. Horford is a better shot blocker and passer and all around player by far right now.
Griffin, Millsap, Ibaka, Aldridge should be rated in that list but it's more guys that can do both.
I just threw that list together to list all the top guys so take it with a grain of salt. It's not really a ranking. It kind of is though.
Horford should probably be at 3 though. Gasol should be up there too although i think he's fallen off a bit the past few years. Horford hasn't.