Recommend flying something you already have if you're trying out Basic for the first time. New season fast approaching!
Better to spend time practicing with another IMAC pilot at the field than spending money or time building a new airplane. Once you confirm you like IMAC, it might be time to invest in something still simple to transport, that will hold up to a couple hundred flights in one season.
You'll get a million recommendations on airplanes to fly...here's one that just came out that looks promising and will probably take you at least through Sportsman with no problem:
Put a canister on a 60cc motor like a DA-60 with the recommended prop like a Mezjlik and you'll score high on sound too.
Most of all...have fun doing it.