I don't know how I missed this the first time around. You'd probably have better luck if you seeded in the fall. Cool season grass seeded in the spring has a tough time making it through the summer. Dutch White Clover may be a good option for you. It's drought and heat tolerant and used to be included in grass blends until the weed and feed products started getting popular. If you have alkaline soil, strawberry clover may work better than Dutch White Clover.

To keep dogs off, you want something fairly substantial. Salal doesn't discourage my dogs, I can tell you that. They love to go crashing through it. Creeping mahonia does to some extent, and that's a local native also. Junipers and cotoneasters are good suggestions, just not the really prostrate ones. Something about knee-high is more likely to keep dogs off. Maybe creeping rosemary, or shrubby potentillas. You could also plant a low-growing hedge as a barrier, and then plant whatever you want for the ground cover.

A relatively narrow 60' length with only a single planting of a very low, ground-hugging groundcover may be a bit more boring than you expect :-) While creeping or woolly thyme are very nice and pretty rapidly spreading GC's, they are rather characterless when not in bloom (and not nearly as great a weed deterrent as a few other GC's). They offer a much better aesthetic if grown on a gradual slope or even on low, rolling mounds. I'd consider adding some hefty landscape boulders to create some contours (and take up some space - you have a lot of real estate to cover) or selecting something with a bit more oomph to it - Rubus calcynoides or Genista pillosa 'Vancouver Gold'. Both will grow and cover far faster than the thyme, have more of a profile and offer much better weed suppression. The Euonymus fortunei 'Kewensis' PJ mentions is also an excellent choice and tolerates sun very well. Growers flats of GC's have become increasingly difficult to locate in recent years and even my best GC suppliers offer them only in the summer months and infrequently and very selectively at that. But with a very low growing, mat-like GC like the creeping thymes, you can easily cut up the typical 3.5" pot into 4 or more chunks, thus increasing your supply. I'd also recommend holding off on the planting of thyme - if that is your choice - until spring or after the worst of the rainy winter. Unless well-established and in extremely well draining soil, it dislikes the amount of moisture we receive in winter. For a 12" spacing (and no boulders) you need 900 plugs/pots - for an 8" spacing, you need approximately double that. With either the rubus or genista, you can easily get away with 16-18" spacing or 400-600 plugs/pots.

I love creeping veronica and want to try some as well. I have thyme between flagstone pavers and while it is drought tolerant, smells great when you step on it, and takes heavy traffic (dogs, lawn mower, kids riding their bikes over it daily), I hate how it leaves obvious dead patches from the previous year's growth and it tends to overgrow (and creep) more than I'd like. It's okay, I'm just not crazy about it and don't love the color when in bloom either. I have a few different varieties and don't go crazy over any of them. I prefer the areas where we planted creeping jenny (moneywart). Some areas get more shade than others, but they're all thriving and withstand foot traffic really well. I've also heard good things about pussytoes, so you might check them out.