I'll take some pics of this later today as I have some sleeves to shorten, but the answer on resewing the sleeve is yes. Shortening a jacket sleeve involves completely taking the whole bottom of the sleeve apart. Every single stitch gets ripped out of there and the vent is remade. It's one of the most common jobs and in the mind of the customer it's nothing, but it's a bit of work, indeed. Way more work than hemming pants, for instance. There's just no getting around it if you want it done right, anyway. If you've got a little vent left after shortening the sleeve, you've got a few options: Sew on 4 traditional buttons and make maybe the bottom two working. Obviously you'd need buttonholes sewn on for this. Or, you could put 3 working buttons on only or perhaps even 2. After all, it is an odd jacket, right? Why not induce a little style into it? Not many are running around with 2 working button odd jackets... Regarding the back length, you shouldn't have material bunching up over top of your seat creating a "shelf". That's a sign that the seat of the jacket is a little too tight. It's not REALLY tight and may not need to be adjust much, but perhaps a little. The back balance does look a little long. This is fixed by shortening the back at the top. These 3 alterations: -Shortening sleeves no matter how you do the buttons, but def more if you want them working -letting out the side seams at the front only -squaring shoulders/shortening back balance are going to cost you a little bit.