Not an ideal answer, but I have tried something similar. I am a tall rider at 195 cm, but a large proportion of my length is in my legs. So my saddle is high and my reach is only average.
On steep climbs on my road bike I have issues keeping the front wheel on the ground, because:
The UCI limits the bike's wheelbase to a certain maximum, which reflects on the bikes available to the public.
As the leg length increases, so does the saddle height.
As the saddle rises, it also goes back because of the seattube angle.
Upshot of all that is the rider's saddle weight is over, and then is behind the rear axle, which subtracts from the front wheel's weight, causing lifty wheel, poor steering and balance, and in extreme cases back flips.
So I obtained this former e-bike and made it more roady. It had roughly 125mm longer chainstays to store the battery pack. With the seat forward, it should have been balanced at a 72% gradient. I rode it up a 35% road and the front lifty was completely gone. Downside, a 20 kilo steel bike was no fun at all going up a hill.
Handling
This bike would not wheelie. I could barely get the front wheel off the deck by moving backward and mashing a pedal.
It steered straight and true and was awesome when riding a long straight road.
Turning was okay, but it was more bargelike than reactive. Because the rear wheel was so far behind, it took a longer wide turn to get around a corner, and the back wheel followed a much different track.
The low BB meant for easy pedal strike too, so I learned to keep cranks level.
For your purposes, you're interested in the front not the back end.
So you want to keep the angle between your saddle and each axle the same. That will preserve the bike's handing as much as possible.
However, increasing the height will make fast stops hairier simply because you're taller. My impression is tall bikes are for show, not practical daily usage and certainly not for racing around fast.
I remember a good answer on this site about modern MTB geometry, where the headset looks way too far forward, but can't find it. For your needs, I suspect a very short stem combined with extending the top and down tubes will be about all you can do.
Trying to change the angle of the forks by extreme amounts will be fairly fruitless.
Idea: How about indirect steering? Imagine sitting in the rear seat of a tandem and steering from the back? There are some great images of an old rear-steer tandem which may give you enough ideas for your own build. It'll still steer like a boat, but it should track okay and self-center like a normal bike.
