BB vs Bet Flop in HU 7-15bbs limped pots

In this warmup I covered BB vs bet strategy in heads up limped pots between 7 and 15bbs on 3 different board types.
These are some of the key ideas:
the shorter we are:

• the more polarized is the range of the BB that reaches the flop
• minus Ax and Kx we have in the range
• more bets SB makes, BB folds more, calls less and raises more (on average)
  As we get shorter on dry boards with a high betting frequency like Ahi and Khi, the BB plays more raise or fold:
• because SB has a very wide range
• because BB has few natural floats (we can't call a bluff so we scratch)
  on coordinated medium boards:
• we have to be more selective with the call range
• we don't win continuing with all the overcards (we only continue with Khi and Qhi with some kind of backdoor equity)