"you were envisioning" is correct and usable in written English.
You can use it when you want to describe a past event or situation that someone imagined or foresaw. For example, "The image you were envisioning was a bright, sunny day at the beach."
Especially because it is not exactly what you were envisioning, this experience will introduce you to possibilities you did not foresee.
It's awesome and exciting because now you have a product that expresses so much of what you were envisioning, and you can finally put that in front of real people.
This is the most common mistake -- and often results in overcooking, meaning your fish will turn into cat food instead of the elegant dinner you were envisioning.
Sizes and placements might not completely match what you were envisioning the first time.
But if you are envisioning a rare African antelope, think again.
Since the majority of your guests would have to travel to Baltimore, what you are envisioning is a destination wedding.
Maybe you're envisioning going to college 2,000 miles from home, but your parents are thinking differently.
If you're envisioning airplane cabin advertising, you probably should banish any old images of battered subway cars with posters for bunion doctors and lawyers seeking accident victims.
"You need to figure out exactly how this is going to work in the world you're envisioning, and that will help you determine the decisions you're going to make," said Julia Chung, a financial and estate planner with Facet Advisors in Langley, British Columbia, in Canada.
If you're envisioning a home improvement that will bump up the value of your home, it's usually fine to finance it — so long as your total loan, including the original mortgage, isn't for more than 80% of the value of the home.
You're envisioning the null set, right?
