When I have to paint landscapes, there're actually all of those listed above. With some more colder blues, like ultramarine and cobalt, but rarely purples nor violets. I do love them for shadows though, the deep aubergine hue, it's pretty awesome, or some greyish cold violets for skies or sees, or any other light reflexions.
That's the challenge, my friends, that's quite a challenge for me to build something around violets I would personally love which wouldn't feel like "I have to", but being more of "Not bad, I could love it".
I still hesitate about this one. More lilac than violet, and slightly less orange, like more warm yellow and some warm red hue which would give a nice orange if I'd mixed them. Which I didn't do, and that's okay. I love the funky graffity-like vibe it has, with all the splashes of colour around, dynamic and young.
Now I have to fill the pages and come back to you sharing the whole project. I just popped up, still in doubt but actually surprised, how it turned out. Not bad, I could love it!