There are several "T5" models listed here:
https://lilygo.cc/collections/t5-series - what size display you want is up to you. I don't think of 4.7" as "too large", for my eyes anything smaller is too small to be useful. This device is interesting:
https://lilygo.cc/products/t5-e-paper-s3-pro - because it also includes a GPS module and a 900 MHz radio module, thus it could run integrated software that includes both SoftRF and SkyView functionality within a single device. That is certainly feasible to develop if somebody wants to. I am not motivated in that direction, since I would rather feed the data from SoftRF into XCsoar (running on a more powerful Android device) which does a LOT more than just display the traffic, i.e., it is a glide computer and navigation aid.