Hi Elisabeth,
In general terms, 1700 is considered too long for a picture book, with some exceptions for well-established authors or non-fiction.
However, it's also not the case to call a book an Early Reader just because the word count is too high for a picture book. Early Readers have very strict guidelines on length of words and sentences.
So, your best option is to decide what you want the book to be and revise accordingly. If you want it to be a picture book, revise ruthlessly, which is easier said than done. But cut out most descriptions on color and scene unless absolutely necessary to the plot of the book. Those things will be taken care of by illustrations. Focus your plot, make sure the main character has essentially one issue to solve. Find a critique group or post on the critique boards here. But 1700 words is too long to post on our boards as 1000 words is the limit. So see if you can cut 700 words or just post the first half. :-)
I also find it helpful to type up text of picture books I love and that have been recently published. Then print it out and compare your typed out text to the print out of the published book. You'll see how much the author left to the illustrator and how masterfully they used their words to set up tension and page turns, etc.
I hope this helps!