Warp ten is infinite speed. How can anything be faster than that?
i agree with you there, warp 15 it is, it will work better with amount of warp nacelles my ship has
Starfleet or whoever changed the warp scale sometime between the TOS era and the beginning of TNG, in the possible future of All Good Things the warp scale was changed (possibly) again to allow for a speed of warp 13.
A century after the Dominion War, sure warp fifteen plus, with the hero ship topping out at warp ten.
Change is good.