One piece is more effective if the combination has qualities that would be impractical to achieve with two separate glyphs — like the rounding of the corners of the counters in the first example.
Two separate glyphs may be a more practical approach if one or the other can be reused with multiple partners — e.g., OC, OG OO, OQ in your second example.
Both approaches have advantages and disadvantages. I do not think there is a single “best practice.”
Comments
Two separate glyphs may be a more practical approach if one or the other can be reused with multiple partners — e.g., OC, OG OO, OQ in your second example.
Both approaches have advantages and disadvantages. I do not think there is a single “best practice.”