Beginners are, or should, be against other beginners (who are most likely also using a TOW rocket) so a weapon's unforgiveness is irrelevant. Even at current damage AND a 3 second reload time, TOW rocket would still be one the most newbie friendly weapons there is. It flies fast, straight, you don't have to hit it directly, it cares very little about positioning and it doesn't create significant amounts of heat. Missing with TOW at its optimum distance doesn't mean that you'd have better luck with Corsair, Hellfires, Sabot or even GL.
Why adding adding 33% more damage to a weapon in exchange for 33% slower reload time is bad, is because you are not trading burst for DPS, you are only adding burst, effectively only buffing the weapon.
It would be superior in corner fights because it's much less about how often you can shoot, but rather how much damage you can trade in an encounter. While in a CQC DPS race 0.75s is a significant amount of time, in a "peekaboo" behind a cover, it's not.
What comes to DPS races, you're dealing 88% of the damage with two slower reloading TOWs in a 50% faster time vs. Firing three faster reloading TOWs. 330 damage at 3 seconds vs. 375 damage at 4.5 seconds. Considering the armor of the mechs, for fights that usually end at 3 rockets would then end at 2, thus saving you time.