If you are subjecting your cover to a sewing machine I have two suggestions for you.
On the front of the cover behind the spindle there is a vertical piece of velcro that is too far back to really hold the spindle strap. Sew on a piece of 2" wide velcro horizontally in front of the original piece. This allows the strap to come around and hold at the position where the cover is in its naturally fitted state.
On the rear, I had a 1" side release buckle that I added a 6" extension strap to, double the end over and sew. Now, instead of the rear end with the hook simply coming up to the ladder lock for adjustment (which is way too short anyway), feed the new extension strap into the ladder lock and the hook end strap into the adjuster of the side release buckle. When you are traveling in icy/slushy conditions and the straps get frozen, you can now unbuckle the hook, remove and then re-buckle the hook to the cover. Ski-Doo does this and I think it makes excellent sense.
Sorry no pictures and I have done 3 covers this way so far.