Moers named the AMG GT4 racecar as one. It will sit below the GT3 customer racer and split the difference between the new GT R and the GT3. A race-ready AMG GT3 costs about $420,000, so expect the GT4 to be a little less expensive to purchase and run, a lot less extreme, and a bit more approachable for the gentleman racer.
As for further street-legal variants, we fully expect a convertible body style to be added soon. That would conceivably double the number of roadgoing models, assuming AMG builds droptop versions of the GT, GT S, and GT R. The GT and GTS would be givens, while the R might be a stretch, especially if AMG follows Porsche's hardtop-only philosophy for models that straddle the realms of road and racing.
New variants means reaching more customers and it also sets the GT up as more of a 911 competitor, giving buyers comparable options across more of the Porsche's range. The 911 famously offers a huge number of models and body styles, with a filled-out lineup usually consisting of about 20 permutations and combinations between coupe, convertible, and Targa bodies, with rear- or all-wheel drive, spread among the base Carrera, Carrera S, GTS, Turbo, Turbo S, GT3, GT3 RS, and sometimes GT2 variants, plus the 911 Cup racecars. The AMG GT isn't quite there yet, with just four models to date including the race-only GT3, but you have to start somewhere.