Re: D&D 5th and Blind fighting
To strike something you can't see... that means you would normally need to make a perception roll (or passive perception success) to identify what square.
Keep in mind... in 5th edition, by default, when you can't see your opponent, you have disadvantage on all attacks. Also, all attacks against you, are given advantage.
The Hermit background gives you a 'Discovery' which is learning something unique and useful. One might suggest if you combine that with accepting the 'Blindness' that perhaps the Discovery could grant you Blindsight ability at 5' as long as you can hear. That would allow you to see/sense anyone right around you. Perhaps an additional ability you could be granted would be an option for a Bonus Action that would be making a perception check (not at disadvantage like usual) which if successful would allow a single designated opponent to be considered within the scope of their blindsight as long as they are within 60' or something like that, until the players next turn.
If the character gets affected by a silence, or can no longer hear for some reason, they function as if normally blind and deaf.
This would mean you would still have significant disadvantages/flaws, but would be able to operate in dark situations better than many, and the blindsight would allow them to avoid being at disadvantage from adjacent melee attacks, and the bonus action would allow them to even track a single ranged opponent.