Your left hand will determine the pitch. So place your finger according to the chord or notes you want to get with this hand only.
You right hand determines the note trigger, its gate (or how long it will sustain), its intensity (velocity) and polyphony.
So, if your right hand picks two notes, their pitches will be determine by the left hand position. Your right hand is responsible to dictate the phrasing of the notes: arpeggiated, legato, staccato, etc.
Like it so far? Me too.
Using a traditional keyboard, split it at C4.
Left hand is below C4 and right hand is over C4.
Now pick a software that let you do splits and a bit of MIDI routing, and use the zone below C4 to determine pitch but WITHOUT note trigger. Over C4 will be the triggers for the notes. If nothing is pressed on the left hand, you would get: EADGBE.
Just a proposal.
left hand = pitch
right hand = gate
There's something natural about this, why don't you try it on whatever controller you have?
Be bold, be original: don't get a guitar.