Is 1500cc of pure fat removed from lipo enough to make a difference?

Not even close!  1500 cc might be enough to remove from an average person the arms.  From the inner thighs and knees and arms you should have seen 3 to 4 times that much, unless you are less than 100 lbs or didn't really need lipo.

For many patient, that amount removed will give a very nice result. Remember, initially you are swollen and won't see your final shape for several weeks.

the amount removed is not as important as the end goal and the type of procedure.  my hi def procedures almost always remove 5L and get very significant improvement (see my IG).  however, if you are large 1500 is very small and if you are small 1500 maybe a lot.  I suggest seeing an expert.  Best, Dr. Emer.