If you decide on gravel, you could use a leaf vac to suck up and shred the leaves. Then you could add the shredded leaves to the compost. The leaf vac's suction isn't strong enough to suck up the pebbles. If you mulch the area, you could just leave the leaves (no pun intended) to decompose and add their nutrients to the soil. However, I noticed that 1 tree is a Cottonwood, which I have. Those leaves I have to vac off my mulch because they don't break down (as you probably already know).
As for privacy, instead of a fence, how about trellis panels and vines growing on them. I don't understand why you can't grow shrubs that prefer shade. Although yews are slow growing, they tolerate full shade and would provide year-round screening.

Thanks for the advice. I've tried using a leaf vac in the past, but I had too much trouble with the twigs from the cottonwood jamming the thing. Maybe if I use it in it's leaf blower mode it would work better. One of the problems with the maple tree is that not all the leaves fall before the snow comes down.

I've also tried yews in the past without much luck (although you can see one small one that survived way in the back). I might give those another shot and be more careful that they get enough water, etc.

Thanks

Re cottonwood twigs - I feel your pain! I usually stand on the twig and yank off the leaves, letting them fall to the ground to be sucked up.

I have a similar senario where I have a path in the shade going to the woods and it is pea gravel. It's not that bad raking the leaves and I do get some sticks from the maples and birch trees. What I hate is the weeds growing. I hand pull those cuz I have a dog that uses the path and I don't want to use chemicls. If you don't want the pea gravel, you could let your leaves and twigs be your mulch, maybe adding grass clippings to it and maybe put down pavers here and there for stepping stones??
As for a privacy shrubs, could you plant rhodadendrons there in between the 2 big trees?

I agree that you could just let the leaves stay where they are and eventually become part of the wood mulch. Or vacuum them off a pea gravel path (which would be very pretty, with an Asian feel)

As for privacy, maybe some tall grasses or clumping bamboos? You could truck in some fill and make berms to raise the level near the property line by a few feet, then plant the grasses. Also, large-growing shrubs (lilac, forsinthia, joe pye weed, rodedendrons (can't spell - sorry). It will take a few years to establish, but could look lovely.

We tried the vac deal on acorns. What a pain. What does work on rock is a leaf BLOWER. I blow all the leaves from nearest my house out into the yard where we can mulch them. I do not suppose you would want to blow near mulch.

i find that, with a mulch path, i can usually rake the leaves lightly off it, without disturbing the mulch. also, i just read that a heavy turf roller will pack mulch down (and also pea gravel, by the way), so it doesn't get raked up or vacuumed away or blown away -- and also prevents the mulch from sagging downhill, clumping up, etc. we have a unique mulch situation, which is turtles coming up from the lake and digging holes in the mulch to lay their eggs! i carefully brush the mulch back into place after they're done. what did one gardener say to the other?? I LOVE YOU VERY MULCH!