Pity i.MX RT1064 is only available in MAPBGA-196 with 0.65mm or 0.8mm pitch; I definitely don't have the skills to make my own board with those. Otherwise, it'd be a pretty darn powerful microcontroller
I didn't read up on RT1064 and I bet it's much better than the RT1010 and RT1020 in LQFP I have experience with but still, those MCUs are made to a price and they aren't that good as they seem on paper, lots of limitations and compromises in their peripherals.
Teensy 4.0 only provides 50 I/O pins and
Teensy 4.1 55, and a limited subset of the peripherals anyway. But the ones it does provide, are pretty much amazing considering the price point and ease of use (4.0 being < USD $20). Not to mention it runs at 600 MHz, and has 512kB+512kB of RAM. (Teensy 4.1 has pads for additional PSRAM, though.) I haven't found the practical upper limit for USB HS bandwidth yet, I only know it is over 200 Mbits/s (25 MiB/s) because even a simple Arduino/Teensyduino using USB CDC ACM in one direction achieves that. I like them.
Sure, there are limitations (and I hear the development of Teensy 4.x took a lot of time and effort, especially the early initialization part), but they're nothing compared to the gains. Personally, I'm not even interested in most of the peripherals; I just want DMA, GPIO, SPI, I2C, USB HS, and lots of RAM; and preferably contiguous banks of GPIO pins so I could DMA out data in parallel to a small display controller, with easy to use DMA triggers. The stuff I do isn't complicated.
I haven't seen anything comparable. The STM32H7 series looks interesting, but requires a separate ULPI transceiver for USB HS. That does not mean they are not available; that's just what this one hobbyist has seen