I ride a 2010 softail custom. I'm looking for a sissy bar that will allow me to keep the stock seat, but also come up high enough to offer back support for a passenger, and my luggage. The stock bar doesn't offer any support, and as far as my luggage goes, I don't really trust it. It looks like it wants to just fly off. Any ideas ? Would I have to swap out my seat ?

 

You could add the Bobtail fender rack,
https://shop.zanottimotor.com/catalo...?sku=53979-07A
and use the bungee nuts to help tie the luggage down.
https://www.hdforums.com/forum/dyna-...ngee-nuts.html

My 86 FXSTC has the old style sissy bar supports that might not look as clean as the newer style, but actually supports the passenger. I have the 14" pad on the taller sissy bar.

Just my opinion, but I think the newer seat is too huge and never cared for it's built-in passenger pad.
I'd be looking at a Mustang or C&C replacement for it.

 

I got the bobtail fender rack. I tried the bag sitting on the rack and it's even worse. If I got a custom seat, would I still be able to use the rack, as they both attach to the fender in the same hole. I'm open to a new seat, I just like the stepped look that the original seat has. Kinda like Mustang "Regal Duke".

 

I have a set of HD luggage that slips over the sissy bar and pad.
So the bags can sit on the seat or the fender rack. Then use bungee cords to tie it down and keep it from shifting during the ride.

The step in the 2 up seats like the Mustang Regal Duke, gives lower back support. The newer HD stock seat looks to have so much padding, the step is almost gone.

 

Here's what I did. About a year ago I removed the backrest...wife says it is more comfortable with out it. It is sturdy as a backrest and I can bungie the kitchen sink to it! lol