I gathered the fastest letters and put them in a race. Who do you think will win? Your options are: E (he's a fast runner, even without gems) O (he can roll at the speed of a race car) P (she travels at superletter speeds when using her gem) Q (she's very quick and agile when rolling) Also, don't ask why Q's ponytails look like that. It's due to the high speed she's traveling at.
Credit 2 Every1, especially @elithepidude for the bases of the gems, @PhonicLover44 for the sprites, and Mike Salcedo for Alphabet Lore.