I found this pattern and thought it has a similar basic structure:
I have never adjusted these many aspects of a pattern before so I thought I’d come here for some advice!
Since the vest is supposed to be oversized, I don’t mind the final garment does not measure exactly the same as the cardigan pattern. I also don’t think this texture would influence the gauge that much.
Very pretty vest that nicely uses the checkerboard pattern.
The sleeve opening is an important point to consider. The sweater pattern has a drop sleeve that will give you a longer shoulder seam and perhaps a wider armhole than you’d like.
There are vest patterns that will get you closer to the look of the pattern you like.
A search on Ravelry will bring up many more choices.
I agree that the vest salmonmac posted will be so much closer and easier to work with.
When planning your project you can add a stockinette buttonband to the width and stitch count of the fronts to get the look. At the armholes too, once you reach the underarm you can add the stockinette sts to work at the same time as the body to give the same finish.
Just remember to put a stitch marker in and jot down how many stitches there are added in each section.