One of my students has a courbette vision; the flaps are very forward and the center of the seat is significantly behind the stirrup bars. It is really built like a strictly xc saddle which is not particularly useful for the average rider.
How about a Duett (they come pretty wide)? Or an Amerigo which IIRC have something about the panel design which is supposed to 'float' over the shoulder....?
There are 2 types of Visions. The "Extra' which has very forward flaps, and the regular Vision. A lot of horses who have big shoulders (and some who don't!) don't like the flaps of the saddle on their shoulders. The tree will be positioned behind the shoulders, but the flaps will still be touching the shoulders and some horses just don't like that! Your best bet is to try as many saddles as possible and see which ones fit well.
I loved the design of the Vision for myself, but I tried it on several horses and couldn't get it quite right. Some of the issues were that the tree points seem longer than a lot of other saddles I've tried, so that created sore spots. It also is not adjustable, which isn't a problem if you know your horse won't change much but for me I wanted something that could be tweaked a bit.
I had a 17.3 hand ID cross that had the biggest shoulders you've ever seen. he went well in a wide county conquest over fences and a county connection on the flat. My current horses are a "hair" smaller but still have great big shoulders -- they also work well in the county for jumping and I've got an albion sl for dressage now.
Be careful with those tree points!!
I have the "Extra" Forward and I agree with what's been said. It's a great saddle for XC and a good one for SJ too. It definitely puts your legs very forward. My horse is a very narrow TB so the flaps don't affect him. I agree with trying this one as well as a lot of other saddles.
They retain their value well if you buy them used, so why not buy one with a wide tree in your seat size and give it a go?
I bought mine used, used it a couple of times, didn't like it much (I found it held my legs too firmly, although it fitted the wide-shouldered horses fine), and sold it for $500 more than I paid for it; profit included elbow grease and a tin of lederbalsam, of course.
I am using a 31 tree Stubben Siegfried with an extra forward flap (VSS?) on my almost 18 hand ISH. I am almost 6', needed the extra forward flap. He does have quite big shoulders on him and it seems to fit him pretty well.
We use County saddles on our IDSHs. One wears an extra wide, two wear a wide, and one has a regular medium width. County has gotten very expensive, but you should be able to find a good deal on a used saddle.