It depends on the context.
There is no single answer to this question.
There are instances where you'd want to use contrasting fonts and there are instances where you'd use the same font to highlight the contrast of the words themselves. End result and target demographic very important.
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What do you mean by ''practising GD for roughly 4 years''?
All of these have issues that should have been discussed in a theory class or two, starting with 2D balance of elements and including color...