I would prefer max 10 ap, but i like things to be distinct.
If you have 100 ap, things will cost like 30-40 AP (for an attack) so that could just as well cost 3-4 ap (with max 10 ap). It would mean the same thing but clutter the interface more/force the player to do more math. You only need higher numbers if you plan to use the extra detail level such as having one attack cost 30 ap and another one cost 34 ap (but i would advice aginast that).
The worst application of number inflation is seen in many (often asian) mobile games where you have atrocities like:
"Super awesome fighter stats"
ATT: 3473
DEF: 2194
SPD: 4381
And then you level up and gets +573 to some stat. I mean who needs all those decimals! (compare to level up 5.73). Those games also like to spam those long numbers on the screen like it somehow makes the game look advanced or somehting. Terrible.