I'm going to open a can of worms here and I realize that. Before I start I want to say that I'm speaking from my own personal experiences and from talking to others that have hunted both fenced areas in SA and "open" concessions.
You have said it in perfect details in your opening post.
Whatever you decide after reading the community inputs here, will again be only your decision.
Not an easy one!
I have similar concerns, for my future hunts.
My input:
1. If you dont have experience, and want trophy 100% after first hunt, then go to South Africa or Namibia, ranch hunting.
But this is not your case exactly.
You have already expereinced this, and have your first tastes of Africa. So the horns are second priority.
2. If you want wilderness expereince go to Zim, Tanzania, Mosambique. Choose wisely your outfiter, and go there. Keep always im mind, then it is about the expereince, not horns. Experience you will have even if you dont shoot. If your hunt is below expectations, you still will have expereince of "modern wild Africa", maybe locals, maybe seeing less game, due to poaching etc. But its modern African reality as well.
There have been reputable outfits, who failed to deliver, reported to this forum. Maybe just becasue of wrong choice of season in wild areas. But failed nonetheless. WIlderness hunt is chance. And thats it.
3. Young PH.
In hunting camp where I was hunting, in Namibia, there were two PHs sons age cca 16. They are all over and up to the neck about hunitng, guns, animals. They live for it.They grew up at the farm. I told my PH when I come next time I want to hunt with them! Youngs are possibly more pasionate. Old PH is more experienced but what the young PH lacks in experience, he makes up with effort and passion. Convesrations are more easy, bonding is much more smooth *then with "old grumpy PH"). (Ok thats my view and expereince, becasue those two kids grew up in bush, and know everything, but thats how I see it.
It could be different if young PH comes from urban area, and start learning the trade at age of 20, but not spending his young years in the bush, and on the farm...)
4. Modern Africa
Times of Ruark and Hemingway are long gone. Modern wild Africa today is diferent. Always keep that in mind. You will not repeat Ruark.
So, go wild, expect experience, choose wisely, and hope for best, dont be dissapointed if horns are not up to the expectations. Compromise if neccessary by hunting something else, then what was originally planned.