Post a picture of the area. Try to get a photo that it is not too dark and line up with the center, at one end of the space showing the overall lay of land. People need to get a feel for what you're facing.

Small inner city spaces like this can be turned into lovely, intimate gardens when they are executed with good design and quality materials. Too bad you are not motivated to learn to lay pavers as a courtyard of them could be the foundation for just such a wonderful garden. A hard surface, like pavers or concrete, would be ideal for your needs.

A less demanding installation would be a path of tamped granular material (gravel) but pea gravel is not the one of choice for walking on. Being that it's rounded, it does not pack and lock tight so that with every step, gravel squishes out from under your feet and makes for walking that is more like trudging. And it scatters from walking, always making a mess of the surroundings.

If you're going to use gravel, you need something like decomposed granite, or limestone screenings. Various gravels are called by various names in different parts of the country. Pay a visit to wherever bulk landscape materials are sold and look for gravel that contains a mixture of particle sizes within the blend. It should contain dust, sand, and chips (angular ... not rounded) as large as 3/8" .... maybe to 1/2" tops.

You would install it in an excavation that allowed for the finished "walk" to have a thickness of 3 1/2" to 4" thick. Install in lifts 2" thick that are compacted hard with a paving tamper. (It's a heavy metal plate -- about 10" square -- that has a handle sticking straight up about 3'+.) Wet each lift, and compact it again.

Another possibility that requires an even lesser skill level for its installation is A path made out of wood-based mulch ... something that is chipped, not pine bark. It would still probably require some excavation as the material would have a finished thickness of about 3". Rake and press it into place. Compact it by walking on it or let it settle from rain over time.

Each and all of the foregoing material types require a rigid edging that will keep the material from migrating away at its edges. Probably the best and easiest to use is steel edging (best to get a professional grade from a landscape material supply house.) It can make straight lines and curves and is pegged to the ground with steel spikes (that come with it) at intervals.

(I should add, another reason I resist the pavers is that there's already the concrete slab, and I'd rather not have most of the yard hardscaped if I can help it.)

There are some ramshackle, amateurish looks that have appeal ... usually good, heavy-duty materials and arrangements ... but can be very patched and mis-matched. Other amateurish lacks a sense of arranging, uses plastic & light duty elements.

Since when is wood mulch neither porous nor natural looking?

Since I am not a professional of any sort I can speak freely. I like the dirt floor. Of course you would get muddy when it rained but I doubt you go out there when it rains.

I am experiencing zone envy of a perverse kind. I love being in California but shade gardens in CA are dry shade gardens. I would love to have a plot like yours that I could fill with the moist shade garden plants. Plants like Astilbe and Dicentra poop out here after their first season. I am told we do not have enough of a chill to make them rebloom. I would make a fancy shade garden of your plot. I have some small boards that I leave outside. When necessary for me to walk through mud, I put them down to walk on. The rest of the time they are out of the way.

BTW and FYI, laying pavers properly is actually an easy project overall. But it requires following certain steps in order. Even though none of it is difficult (except for that it is work!) it is helpful to see others do it first. A good, short video showing the basics by This Old House can be seen here...

How about wood mulch interspersed with shade-friendly plantings? Another concern I have about the paver project (watched the video, thanks for posting) is if I'm digging down 6 or 8 inches, that's a lot of soil that has to go... somewhere, and again, I'm in a city in a townhouse that's attached on both sides. (No option of wheeling it around the side of the house in a wheelbarrow!)

Not sure of exactly what you mean by interspersed. I think it would work best if you kept your walk pathway more or less central with planting beds on both sides. (As opposed to a broad pathway that had beds scattered around in it. Or plantings all on one side and walking path on the other.)

I'm using the word "path" without restrictive meanings. You must connect two ends of the yard for someone to walk from one area to the other, so therefore need a path. You said you want plants somewhere so they must be arranged somehow within the path, to the side of it, mixed up in it ... or whatever else version you can conjure up. You might say what percentage of square footage you'd like to devote to plantings vs the total space. (Dimensions of the space would be useful.) Or you could post a loose sketch of how you might approach connecting the two ends of the yard, showing where any plantings go. Maybe you want less planting than I'm imagining you might want. I don't know. You haven't said.

How about a boardwalk raised slightly off the ground, with ostrich ferns planted on either side. It would look lovely from above and feel great to walk "through" it. BTW is that a bridge I see in the distance? What a great vista! Make sure to plant/prune to reveal it!

This is very reminiscent of millions of small town gardens over here, including my own. I really would urge you to have a hard scaped area rather than gravel or mulch. Not a path as such but a route from one end to the other. In a small garden like that the ground takes a hammering in all weathers - and yes one does need to go out there in the rain sometimes. Even in snow you might need to go and fix something at the end of the garden. Maybe fill bird feeders? Batten down the furniture? Since your barbecue is near the house and the table and chairs are at the other end there will be plenty of tramping up and down. In the autumn you can just sweep your garden instead of trying to get rotting leaves out of gravel or mulch. You can grow low plants between paving stones if you wish. And you can have plants spilling over the edges without the hassle of keeping them out of mulch or gravel. Conversely you could spend a lot of time getting weeds out of mulch or gravel. And it is much easier for anything with wheels like a barrow or garden cart. In WInter your garden will still have structure.

My planting beds have got broader over the years and the paved area narrower. But we still need that central hard surface for traffic. I would get some quotes for installing different kinds of paving before dismissing the idea.

I think the OP is looking for a steppable ground cover. What would work in her situation - ajuga?

Since this thread is more than a year old, my guess is the OP has already done what is going to be done. Personally, I've found pavers to be much easier than expected, so that's what I would go for.

Duh - I saw May but not 2015 ;-) I wonder what she did in the end.

Here's what I ended up doing for those of you who were curious. I dug out and turned over about 2 inches worth of dirt, which was about the most that it was practical to remove on my own. I tamped down the dirt with a tool. Then I divided the area into two parts: a section near to the house that I would use for grilling, and would cover with pea gravel, and central section that I would cover with pine bark. I bought some granite blocks and used them to lay down in edging to separate the two areas. Then I bought gravel and bark, and laid them both down a few inches deep. It's been in place for about a year, I believe I did the work last June. This spring there were a few weeds coming up in spots but nothing that was very difficult to pull. The overall effect is a little rough, but it looks a lot better than what was there before, which was basically dirt full of weeds, and it works for my purposes. Also, because the surfaces are porous it helps absorb rainwater and avoid some of the flooding issues that some of our neighbors have. Here are a couple pictures. Thanks everyone for the advice last year!

I like that, jbrooklyn. The small trees and shrubs make a peaceful, private retreat. Very nice.