Ok, I will justify why I think those two tweaks are needed.
First of all, as Grumbs mentioned already, crossbowing is the only class that apart from the WPF, doesnt require anything else, which makes it the best ranged weapon for hybrid builds.
Throwing and Bows require power throw, and power draw, which means things.
If you are a thrower and want to inflict serious damage, rather than trolling, you need to spend at least 6 points into power throw, which leaves you with 3 less attribute skills, or 0 IF.
The same applies for archery.
So yeah, power draw for crossbows is a must.
Now regarding the shields, don`t you find it redicoulus that a guy with 3 STR can carry a huscarl shield? And apart from that, high agility shielders receive 2 bonuses.
1. High speed bonus damage, due to the high agility/athletics
2. Durable shields
On the other hand, high damage is justified, because the player invested on a Strength build, so yeah, I prefer strong shielder because of their build, rather than left swing spammers.