this is absolutely very vivid, and not without the beauty of imagination's bit that adds much to its poetic ingredients. I like it so much.
One suggestion, I think you need to be more specific with "the past"…"the present", and "the future". I bet you have your reasons to drop the article 'the'
Other than this, this is a piece that I wish I had written.
Thank you for sharing your talent. May colors bring life to your space, always.

I am a romantic, as you surely are in the beginning of this poem. Part of that is too often overuse color in our words and images to set the tone. For me you have 2 poems working here. I prefer the second:

VANTAGE POINT

I hang a frame on the wall
where artists come and splash
colors and shades of their will.

On my frame, an empty space
I invite who pause to see
"Fill this space with your colors
let others be your eyes",

losing myself in the crowd
my hungry eyes eagerly feast
colors that others splash
in the vacant space of time.

The first 3 stanzas build up to that but are more ornamental, with a vague image of the future being on dotted lines, not connecting to me with the lushness of the " Poesie of Nature " mixed in.
(I also punctuated to better indicate the second stanza was a new sentence.)
My take, a fellow romantic.

using that tiny interval between past and future as an empty canvas to be filled by the 'colors' of our free will is very good........stan