You didn't mention where you lived, important to know because if you live in colder climates as you'll have to go deaper to avoid heaving when the ground freezes. In warmer climates dig down 6", compact, lay down gravel compact to 2" then pour up 4" of concrete. You might get away with 3" with reinforcement, but when you compromise you run the risk of failure. May I suggest mixing in concrete stain for coloring, go to a supplier even ACE Hardware or the internet instead of the fruity colors that Home Depot carries. Also instead of using that garden fiber board which really isn't that flexible try making a metal form for a more natural irregular shape, also stones bigger than 3 feet will not look that natural in my opinion. Also don't worry so much about having straight verticle edges, real stones don't and you're going to fill the gaps with soil and vegetation that will hide a lot of your sins. Lastly, you cannot just pour the concrete over the roots. They will continue to grow and lift and crack the patio. You may be able to just cut them out if they're in the way but an arborist would be the best to ask, as you could injure or kill the tree if done incorrectly. Weakened trees can topple over in storms; improperly trimmed trees can contract diseases.

A 2 part epoxy paint will be your lowest cost protective surface. The slab has to be old enough, then you etch and roll it on to apply. It's not hard to DIY at all, and it stands up to everyday wear and tear and even true "gear head" type of use. We did it in our garage/shop 13 years ago, and it's just now having some flaking/lifting in the hard use bays. The walkways look brand new when they are mopped. You definately want the finishers to do a broom finish first if you are concerned about slipperyness as the epoxy's non skid additive (basically sharp sand) makes the floor difficult to clean. We used it in the car lift bay in case any of the dripping fluids made a slippery spot, and for several years, you could barely sweep the area, and mopping couldn't be done at all as the sand snagged the mop to the point of immobility.

First, you double posted this question. Please delete the other one. I do not know if there is a way to fix this problem. I do know that the contractor who did the work should not have scheduled a pour when rain was forecast. They also should have better figured how much concrete was needed so the second truck was there for the other half of the pour. Uneven surface and a bad texturing suggest a lack of experience. You did not get the fix you were promised. You may have to contact a lawyer to give your complaint some teeth. I'm sure you do not want to pay more money to get the job done right, but sometimes there is no choice. This answe should bump your question to the top of list again, so perhaps someone with more concrete experience can explain what can be done to fix this.

Hi watertoiceXI, If you live in a town that has a government you may need a building permit. Sometimes the town government has an engineer or equivalent who can be helpful with your plans. I received some good help from the city engineer on a retaining wall project that I did. He changed my plan to change 1/4-inch rebar to 1/2-inch rebar and had me use more rebar than I included in my original pencil sketch. Thanks to their advice my retaining wall was much better and more stable. And I had a building permit for it. Their charge was quite reasonable. They did a couple of "inspections" during the project. The wall was near the property line, but all on our lot by a foot. So I didn't have any trouble with our neighbors. It's a good idea to have your town government on your side. ZM