How about a class feature for DnD 5e! Here is a fighting style for your Fighters and Rangers.
When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to attack rolls with that weapon.
Thoughts?
Let’s splash some solarian into the solider in Starfinder
A Touch of the Stars
You have spent time the void and among the stars. You’ve learned what power lies there and have taken some of it into yourself. You and the solarians share a bond that few can ever understand.
Gift of the Stars (SP) 1st Level
You gain a solar manifestation of a solarian at 1st level.
Growth of your gift (SP) 5th Level
Increase your manifestation to that of a solarian of 5th level
Approaching the Power (SP) 9th Level
Gain an bonus feat or increase your manifestation to that of a solarian of 9th level
Power of the Stars (SP) 13th Level
Increase your manifestation to that of a solarian of 13th level.
Radiance of Power (SP) 17th Level
Gain the solar manifestation of a solarian of 17th level.
Some people at a recent game were made because they couldn’t fight with two weapons at once when doing an opportunity attack. Let’s fix that for a fighter with a fighting style!
Dervish
While you make an opportunity attack, you may make an attack with your off hand weapons following all the rules for two-weapon fighting.
Thoughts?
The designers of DnD didn’t want to use shields to shield bash. I DO! Let’s make that happen a different way!
Shield Bash
When you have a shield in your off hand, you can use it as a weapon as if you were performing two weapon fighting. You do not get to normally add your Strength bonus to damage when you use this ability unless another ability would allow you to. A regular shield does 1d6 bludgeoning damage on an attack and you are considered proficient with the weapon if you have this ability.
Thoughts?
How about a fighter’s fighting style that works like the previous feat?
Nimble
When you start your turn engaged with any number of enemies, you can disengaged as a bonus action.
Thoughts?
What happens when you don’t want to be a monk, but you also don’t want to be sword fighter? What if you don’t want to use feats or multiclassing to make that happen…
Instead of attacking with a weapon, you my choose to attack with your body instead. You count as proficient with any strikes made with your own body and use damage equal to a monk of your level. Much like attacking with two weapons, you can make an additional strike, but you do not add your Strength or Dexterity modifier to the second strike.
Thoughts?
If you can thing through your actions, you can also throw caution to the wind!
Impulsive
When you take the attack action, you can forgo your reaction for this round,from the start of this turn until the start of your next turn, to instead gain an extra attack as part of this action. You add all modifiers to the attack and it’s damage as normal.
Thoughts?
How about someone who thinks through his/her actions instead of charges in? Let’s make that happen…
Calculating
When you take the attack action, you can forgo your first attack as part of that action and instead gain an extra reaction this round. You can take this reaction at any time until the start of your next turn. Also, if you gain an extra attack via two weapon fighting, you must give up the attack that has your ability bonus added into damage.
Thoughts?
Watching my players play some DnD 5e, I thought this fighting style up watching my poor two weapon fighter miss way too many times.
Double Chop
When you wield two weapons, you may forego your second attack to make one attack roll. If you do, you gain advantage on a single weapon attack. Class features, abilities, spells, and other effects such as a rogue’s sneak attack do not trigger on advantage gained in this way.
Thoughts?
Let’s keep building on what out there for fighters, paladins, and rangers.
Sword and Shield
Once per turn you are wielding both a shield and a one-handed weapon, choose one of the following: Get a +1 bonus to AC, +1 bonus to attack rolls, or reroll once this turn any weapon damage dice that are a 1 keeping the second result.
Thoughts?
Throat Punch Games 