sounds like they(the inst.) thought you were capable of going to the next step or skipping a step in your progression, are you using a sim to practice? were you hitting the field a couple times a week.
learning to fly is different for everybody some catch on quicker than others good to not go to fast or you will be throwing your cash down the toilet.
after flying my trainer nearly to death I was getting bored with the slow flyer and was a little worried about what level I was at, I had one of the better pilots take my next plane up for me and go over it trimming it and just a general check out after the second flight I thanked him for his time and the trainer has been collecting dust ever since.
if you go with a high performance sport plane get some help, practice on the sim if you have one, and by next spring you will be ready to give it a try, just remember they are not the self recovering easy to fly trainers you have been using you have to be on the ball all the time or your new winter project will just be another pile of trash to clean up.
if you are looking for a tail dragger then the sig something extra is not a bad choice the arf is 199$ the kit which is a good first timer build is about 80$ + glue and covering.
there is nothing wrong with being a little adventurous as long as you know your limits and seek the help you need to be successful