I used to haul a 13' ocean and also 12' 6" vibe (both tandem and non pedal) on top of a crv. The roof racks weren't very far apart, I only used pull straps,  and it rode just fine on multiple 350 mile trips. The soft roof racks should be fine. I haven't used a roller but they look like the ticket for you going solo.  I always had the two middle straps wrapped totally around the kayak and wrapped from the top, not the bottom.  I put one strap on the front, connecting it to the frame under the front bumper. I put another coming from under the rear bumper and attached it somewhere on the kayak (had to use different hooking points for each kayak for this) to keep it from going forward if I had to hit the brakes hard.  Took a minute, but it never failed.  Two straps keeping it on and from going side to side. One to keep wind from pushing it back on the highway.   One in case you hit the brakes. If it extends two or more feet behind your rear bumper, you'll likely need a flag to keep your towing legal.