This sounds great in theory -- but after 200+ dives in this suit I'd never recommend it to anyone. Given that the suit is around 2K you can spend a little more (or less) and get a custom made to measure suit.
Which version of the Fusion do you have? The one I have is made from Aircore fabric and I have been diving it regularly weekly for a year and I have not had any significant issues with it and find it comfortable. Also, here in Europe it is not as expensive as it would cost in the US. Here the suit costs @ 1600 euros.
But you are correct that there are good suits that can be had made-to-measure for a bit more or less depending on material and options/features.
I will say that the thing I like about the Fusion suits is that they adapt if your body morphology changes. I have lost 50lbs since I purchased my suit and I don't find it has significantly affected how the suit dives if at all. I like the fact that I don't need to invest in a new suit just because I lost weight, or if I gain some back. The cut of the drysuit layer combined with the outer skin will more than accommodate any changes caused by my metabolic activity or lack thereof.
My wife just a ordered a made-to-measure suit from a local shop a week and a half ago. My biggest concern is that if she loses or gains weight the suit will not fit and the investment will be bunk, she will have a suit that will be really hard if impossible to sell. That is the reality when you go the custom suit route....and that should be a factor one considers if/when making an investment in custom made drysuit.
-Z