I would think warfare/leadership skills are meant for leaders/shotcallers... Why would you put a limitation if they wanted to stay away from the front line, and use light armor.

Why hasn't this been implemented?

Yes!
Guilds can engage in conflict by paying a fee to declare war on another guild for a duration of one week, costing 100k. If a guild wishes to avoid war, they can pay 100k to peacefully conclude the potential conflict. This system encourages guild members to contribute to their guild funds, whether it be for resolving conflicts or initiating wars with other guilds.

Ultima Online required 5 murder counts to go red.
Albion Online requires -20,000 reputation to lose access to yellow and red zones.

Current system would be similar to saying you get 5 murder counts, or getting -20,000 reputation, when deciding to go evil.
This is bad. This needs to be changed.

Suggested change:
Instead of immediately going to 0 karma when switching to Evil.
Lose 5,000 karma when going evil, instead of wiping out all your karma.