3sd reduces the level of monsters in your HAND I repeat Hand not FIELD so in theory this wouldn't work (gift of the martyr part would though) also we already have a few non toon direct attackers that don't blow themselves up after use so what's the big Deal?
By your silly logic Servant of Catabolism is also broken lol since you can achieve a otk using the above combo you mentioned xd actually you know what let's just ban any card that allows direct attacks :p
we already have menace from the deep skill that allows 4 star or lower monster to attack directly when umi is activated, almost similiar to this card effect. but i never heard anyone got kog with that skill.
Gladiator Beasts don't need to be more powerful. (And yes, this does help them quite a bit. Being able to hit directly instead of risking ATK-dropping Traps is a big deal, especially in a 4k LP format where poking a few times with Bestiari/Laquari will game someone.)