When do you think you decide to either do bio/tank, or do mech instead?
IMO, I think it depends on the map and its size. I would do mech on smaller maps such as Ohana because it complements mech's immobility and its earlier strong timing. For example, a common mech push with 2/2 will hit Zerg much earlier on a map like Ohana than on a map like Metropolis. For bio/tank, I would stick to larger maps because mech isn't as effective on it and drops are very effective (especially multi-pronged) since the zerg army will have to move back and forth for drops (travelling long distance) while you could push and kill their expansion and just fall back, taking an economical advantage.
However, don't feel compelled to do one style over another, just take note of the pros/cons of each style on different maps. This can be used in the metagame as well.
Just as a future reference to any mGG players, I can personally help you become a better player as a whole (like coaching?) instead of just answering questions here and there, but the choice is yours and i don't mind either.
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Previously known as Spirit
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