Most small trees grow somewhat slow, so your request for fast but no more than 30' is somewhat at odds with each other. Velvet Ash might meet your requirements but it is not normally considered a quality tree. Digger Pine is native to southern Cal. Huisache and Mesquite have a desert-look.

How about a Tecate Cypress Cupressus forbesii or a Cuyamaca Cypress C. stephensonii? Both are endangered local natives for you, planting them will assist conservation (and they also look nice).

Resin

If site has right soil conditions and other factors for them and poster does not mind the limitations of evergreen conifers, including constant shade, resin production and persistent litter.

Evergreen conifers are not usually what people have in mind as shade trees.

So far I like the Mesquite & Chitalpa trees, they are pretty fast growing, and don't get too large, and will go with my desert landscape in my back yard. I really have to stay within the size bracket i listed above, as the space is small. i forgot to mention i'm in Southern California.

would like to hear more ideas!
thanks for you responses

Mesquite and chitalpa are not going to provide much shade, try standing under one if you are ever able. Pistacia chinensis can be your friend (male cultivar is non-invasive), a true shade tree that will grow well in a desert. It has strong wood and needs to be pruned early on, to retain a central leader.

It's not likely to get much larger than thirty feet where you live. I really like mine, it gets lots of compliments, and is considered a very "earth-friendly" tree by Texas A&M- "doesn't require pesticides or lots of water". The root flare should be exposed on all trees when planting and plant in a wide, shallow hole. Mine gets lots of compliments. Good luck.

I have a Chilean Mesquite and it provides an abundamount of shade. It is a beautiful but very messy tree. It would work well in a place where it’s debris won’t fall over driveways, paths, or the entrance to your home. Bees and birds love this tree, and it is thornless.

Western Soapberry or Texas Persimmon!

How about cork oak? (if you're able to find it)

As far as desert trees, I think you're thinking of Palo Verde. I think it would meet all your needs.

If you were willing to have fruit, a fig tree could be another option, but they can get messy if you don't harvest all the fruit before it falls to the ground (unless you got a male fig tree). Pakistan mulberry might be another option, this variety is more tolerant to heat, and mulberry trees have beautiful shade leaf foliage, but again, if you don't pick all those mulberries it can be messy.

Last one to mention is a "California pepper tree" (actually originates from Peru). It's a medium-fast grower and is fairly drought tolerant. But a word of caution, if you do supply it with a lot of water for many years and it does grow big, but then it goes years without any water at all, it will suffer drought stress and become susceptible to disease. Only the bush-level trees that haven't grown to a huge size are truly fully drought tolerant. They can drop a lot of leaves and little red berries, so can be a bit messy. Pepper trees also put out a lot of surface roots, so it's unlikely you're going to plant anything below it. Before you plant one, I'd rub the leaves across the top of your hand because there are a small number of people who have a contact allergy to the leaves. They can be a beautiful medium small tree.

I have recently become enamoured of the stylnolophium, or Japanese Pagoda Tree. Has everything, I think, including a bloom season much later in our summer (always a plus). Sculptural, spreading, graceful (a bit slow to reach flowering age though).