Revision rhinoplasty to lift lateral cartilages to change a narrow nose to a rounder and sloped nose?

You had a pretty nose before your rhinoplasty, and now it sounds like you have had ?two surgeries on your septum.   I agree that it is unlikely that there is more septal cartilage to harvest, and to modify your tip would likely mean adding cartilage,which might mean needing to harvest a rib graft.  Making small changes to the nasal tip on revision rhinoplasty can be very challenging, because the healing process is not fully predictable, and there is scar from the original surgery which makes the tissues stiffer and harder to manipulate.  I would wait 12-18 months before even considering surgery, and then consult with a surgeon experienced in revision rhinoplasty.  It is impossible to determine how difficult the surgery would be without an in person consultation, but from what I can see on your photos, I would probably discourage you from having a revision. 

...are you sure of that? IMHO your nose has experienced a good change and, if any criticism should be issued... would be to the over projection of your tip, I would have shortened the medial cruras of the alar cartilages to shorten your tip lenght, which now is disbalanced from the dorsum.If you are sure you want to obtain such effect it is possible; the donor areas to harvest the grafts are normally the ears, behind them and from the conchas.But for this purpose you need a very very good surgeon experienced in revisional rhinoplasties and mastering cartilage tip grafts.Think it twice, my advice.