A photo a situation like this would be very useful. There is always something that can potential be done but ere are a number options also the timing will vary from case to case.
It sounds like you have had what many rhino docs call a tongue and groove technique, which can do a number of things including shortening a hanging columella. Most docs will suggest a full year to let things settle and get the full definition, but if you are unhappy at 6 months I can't imagine that will change in the next 6 months.Yes there are techniques to restore more length and balance to your columella and infratip lobule. Some are simple, like little slivers of cartilage that are columellar plumping grafts, and some are more involved. It might be that your best solution is actually restore length to your septum, using precise septal extension grafts (usually graft material taken from your septum). The key is to communicate with your surgeon, make sure you are both on the same page, and proceed with confidence.
A revision rhinoplasty will probably be needed. The items you mentioned you can be referred by a very experienced revision rhinoplasty specialist who does many of these procedures. I would need to see pictures taken as described on my website and those of others to give you a more informed answer.
A full set of facial photographs are required to make a determination about a complicated procedure such as a revision rhinoplasty. Revision rhinoplasty is more complicated and more expensive than a primary rhinoplasty, because they take longer to perform. It is also best to wait at least 1 year to allow all of the healing phases to be complete for embarking on another procedure on the nose. A closed rhinoplasty approach can accomplish your goals, however look for a surgeon who specializes in closed revision rhinoplasty.