Hi Jeán! Thanks for sharing your build!

Yes, the Maytech motors work great and so does the Flier ESC.

The battery voltage shouldn’t exceed the limit of the ESC which is 8S for the Flier twin-motor ESC. Any battery configuration up to 8S will work just fine. However, the top speed of the motor is directly proportional to the battery voltage so with a 6S battery you’ll have 6/8 or 25% lower top speed compared to a 8S configuration.

The battery Ah rating only impacts your range so anything that fits your budget will work just as fine.

Most of the RC battery packs are able to deliver enough current for all of the hub motors. For example, the Maytech 90mm motors have a maximum power output of 450W or 900W with two motors. So the battery pack needs to deliver a maximum of 36A (900W/25.2V). This 6S Zippy 3.3Ah battery is rated at 35C or 115A of discharge current (3.3x35A) which is three times more than you actually need.

Let me know if you have any more questions.