This might be another example of someone saying they’d like a glass of water and me blasting them with a fire hose… but here’s something else that might help(?)
Something that composers did to try and break new ground in composing in new keys/scales was use specific key signatures - so if you did want to write a piece in (for example) Dorian with a flat 2… you just plug those 7 notes into the key signature.
D dorian flat 2 would be a key signature of one flat - Eb. (Differentiating it from the F major key signature.)
This happens to share a key signature (as do all 7 note scale key signatures) with C melodic minor, Eb Lydian Augmented, F Lydian Dominant, G Mixolydian b6. A aeolian b5 and B altered.
So even when you customize a key signature to create a new palette of notes for your composition, no one knows what key center / root center / modal center you’re choosing from the available options until you make the music and they can see it on the page or hear it.