Personally I did watch the first part of the Jackson's Lotr and oh the horror. I wish I could erase my memories :/
Whether or not it would have worked, who knows, but it almost certainly would have been something far, far, better than the thinly-veiled amusement-park ride that the Hobbit movie ended up turning into under Jackson's tutelage.
[Yeah there are lots of "what ifs" in the world, but for a while, a GdT Hobbit actually seemed like it was going to happen...]
If it were only that... let's not forget the major changes in the story and the reintroduction of LOTR characters who had nothing to do with the story in the first place. It does not make any sense at all if you have ever read the book.
At least the LOTR movies kind of followed the story, but the Hobbit is just something else altogether.
I will say I actually enjoyed the LOTR's prequel content in The hobbit movies (e.g. meeting at Riverdale, battle at Dol Guldur, etc). It was the terrible love subplot, family issues (Legolas daddy issues), newly constructed bad guys that made no sense (Azog, et al), the final battle's numerous plot holes, and the movie's overall pace (LOTRs left a lot of "breathing room" in the plot, it had a good set of beats between high pace and low pace content, The Hobbit was high octane all of the time, it was exhausting).
I don't disagree with this, but I think if GdT had directed, he would also have had a lot of influence over the script and general direction the movie went in. He's not just a hired gun.
Sadly, we'll never know for sure... TT