Proposed Rule improvement. - Bonus reaction

As an optional rule, a character who has already used their reaction may take one additional reaction before the start of their next turn. If they do so, they lose their action on their next turn. This represents overextending yourself in the moment by reacting again at the cost of future momentum.

This rule preserves 5e’s action economy by trading an immediate defensive or tactical benefit for a significant drawback. It enables cinematic clutch moments (extra deflection, parry, or counter) without increasing damage output or allowing reaction spam, making it especially useful for survivability-focused abilities like a monk’s Deflect ability.

Thoughts?

I'm not fond of alternate Homebrew & House Rules pertaining to trading future action for immediate reaction. 

Try asking in homebrew & house rules.

This doesn't sound like it would ever be worth it. Why would a wizard trade their action to cast Fireball to cast Shield, and why would a Fighter trade Extra Attack to make an opportunity attack?

Quote from Maruntoryx >>

This doesn't sound like it would ever be worth it. Why would a wizard trade their action to cast Fireball to cast Shield, and why would a Fighter trade Extra Attack to make an opportunity attack?

 The wizard may need a Shield or Absorb Elements to survive until his turn comes up, a Fighter might have Sentinel which would keep the opponent from escaping or a Topple/Slow weapon that might keep the opponent nearby for other party members to attack.  I can see reasons.